diff --git a/Tests/__init__.py b/Tests/__init__.py
index 9e94e63..956e0a8 100644
--- a/Tests/__init__.py
+++ b/Tests/__init__.py
@@ -1,3 +1,29 @@
+import logging
 import os
+import warnings
 
-TEST_DIRECTORY = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
\ No newline at end of file
+TEST_DIRECTORY = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
+
+PROJECT_DIRECTORY = os.getenv('PROJECT_DIR', os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+# get the logger instance
+logger = logging.getLogger("pyVertexModel")
+
+formatter = logging.Formatter(
+    "%(levelname)s [%(asctime)s] pyVertexModel: %(message)s",
+    datefmt="%Y/%m/%d %I:%M:%S %p",
+)
+console_handler = logging.StreamHandler()
+console_handler.setFormatter(formatter)
+logger.addHandler(console_handler)
+
+logger.setLevel(logging.DEBUG)
+logger.propagate = False
+
+
+# Function to handle warnings
+def warning_handler(message, category, filename, lineno, file=None, line=None):
+    logger.warning(f'{filename}:{lineno}: {category.__name__}: {message}')
+
+# Set the warnings' showwarning function to the handler
+warnings.showwarning = warning_handler
\ No newline at end of file
diff --git a/Tests/test_vertexModel.py b/Tests/test_vertexModel.py
index 24fe329..9c6622f 100644
--- a/Tests/test_vertexModel.py
+++ b/Tests/test_vertexModel.py
@@ -12,9 +12,8 @@
 from src.pyVertexModel.algorithm.vertexModel import create_tetrahedra
 from src.pyVertexModel.algorithm.vertexModelBubbles import build_topo, SeedWithBoundingBox, generate_first_ghost_nodes, \
     delaunay_compute_entities, VertexModelBubbles
-from src.pyVertexModel.algorithm.vertexModelVoronoiFromTimeImage import build_triplets_of_neighs, calculate_neighbours, \
-    VertexModelVoronoiFromTimeImage, add_tetrahedral_intercalations, build_2d_voronoi_from_image, \
-    populate_vertices_info, calculate_vertices, get_four_fold_vertices, divide_quartets_neighbours, process_image
+from src.pyVertexModel.algorithm.vertexModelVoronoiFromTimeImage import build_triplets_of_neighs, \
+    VertexModelVoronoiFromTimeImage, add_tetrahedral_intercalations, get_four_fold_vertices, divide_quartets_neighbours, process_image
 from src.pyVertexModel.geometry.degreesOfFreedom import DegreesOfFreedom
 from src.pyVertexModel.util.utils import save_backup_vars
 
@@ -239,21 +238,6 @@ def test_build_triplets_of_neighs(self):
         # Check if triplets of neighbours are correct
         assert_matrix(triplets_of_neighs_test, mat_info['neighboursVertices'])
 
-    def test_calculate_neighbours(self):
-        """
-        Test the calculate_neighbours function.
-        :return:
-        """
-        # Load data
-        _, _, mat_info = load_data('calculate_neighbours_wingdisc.mat')
-
-        neighbours_test = calculate_neighbours(mat_info['labelledImg'], 2)
-
-        neighbours_expected = [np.concatenate(neighbours[0]) for neighbours in mat_info['imgNeighbours']]
-
-        # Check if the cells are initialized correctly
-        np.testing.assert_equal(neighbours_test[1:], neighbours_expected)
-
     def test_obtain_initial_x_and_tetrahedra(self):
         """
         Test the obtain_initial_x_and_tetrahedra function.
@@ -266,11 +250,11 @@ def test_obtain_initial_x_and_tetrahedra(self):
         vModel_test = VertexModelVoronoiFromTimeImage(set_test)
 
         file_name = 'LblImg_imageSequence.mat'
-        test_dir = 'Tests/data/%s' % file_name
+        test_dir = 'Tests/Tests_data/%s' % file_name
         if exists(test_dir):
             Twg_test, X_test = vModel_test.obtain_initial_x_and_tetrahedra(test_dir)
         else:
-            Twg_test, X_test = vModel_test.obtain_initial_x_and_tetrahedra('data/%s' % file_name)
+            Twg_test, X_test = vModel_test.obtain_initial_x_and_tetrahedra('Tests_data/%s' % file_name)
 
         # Check if the test and expected are the same
         assert_matrix(Twg_test, mat_info_expected['Twg'] - 1)
@@ -326,83 +310,6 @@ def test_add_tetrahedra_intercalations(self):
         # Check if the test and expected are the same
         assert_matrix(Twg, mat_info_expected['Twg'])
 
-    def test_build_2d_voronoi_from_image(self):
-        """
-        Test the build_2d_voronoi_from_image function.
-        :return:
-        """
-        # Load data
-        _, _, mat_info = load_data('build_2d_voronoi_from_image_wingdisc.mat')
-        labelled_img = mat_info['labelledImg']
-        watershed_img = mat_info['watershedImg']
-        main_cells = mat_info['mainCells'][0]
-
-        # Test if initialize geometry function does not change anything
-        (triangles_connectivity, neighbours_network, cell_edges, vertices_location, border_cells,
-         border_of_border_cells_and_main_cells) = build_2d_voronoi_from_image(labelled_img, watershed_img, main_cells)
-
-        # Load expected
-        _, _, mat_info_expected = load_data('build_2d_voronoi_from_image_wingdisc_expected.mat')
-
-        # Assert
-        np.testing.assert_equal(triangles_connectivity, mat_info_expected['trianglesConnectivity'])
-        np.testing.assert_equal(neighbours_network, mat_info_expected['neighboursNetwork'])
-        np.testing.assert_equal([cell_edge+1 for cell_edge in cell_edges if cell_edge is not None], [cell_edge[0] for cell_edge in mat_info_expected['cellEdges']])
-        np.testing.assert_equal(border_cells, np.concatenate(mat_info_expected['borderCells']))
-        np.testing.assert_equal(border_of_border_cells_and_main_cells, mat_info_expected['borderOfborderCellsAndMainCells'][0])
-
-    def test_populate_vertices_info(self):
-        """
-        Test the populate_vertices_info function.
-        :return:
-        """
-        # Load data
-        _, _, mat_info = load_data('populate_vertices_info_wingdisc.mat')
-
-        # Load data
-        border_cells_and_main_cells = [border_cell[0] for border_cell in mat_info['borderCellsAndMainCells']]
-        labelled_img = mat_info['labelledImg']
-        img_neighbours_all = [np.concatenate(neighbours[0]) for neighbours in mat_info['imgNeighbours']]
-        main_cells = mat_info['mainCells'][0]
-        ratio = 2
-
-        img_neighbours_all.insert(0, None)
-
-        vertices_info_test = populate_vertices_info(border_cells_and_main_cells, img_neighbours_all, labelled_img,
-                                                    main_cells, ratio)
-
-        vertices_info_expected_per_cell = [np.concatenate(vertices[0]) for vertices in mat_info['verticesInfo']['PerCell'][0][0] if len(vertices[0][0]) > 0]
-        vertices_info_expected_edges = [np.concatenate(vertices[0]) for vertices in mat_info['verticesInfo']['edges'][0][0] if len(vertices[0][0]) > 0]
-
-        # Assert
-        np.testing.assert_equal([vertices + 1 for vertices in vertices_info_test['PerCell'] if vertices is not None], vertices_info_expected_per_cell)
-        np.testing.assert_equal([np.concatenate(edges) + 1 for edges in vertices_info_test['edges'] if edges is not None], vertices_info_expected_edges)
-        np.testing.assert_equal(vertices_info_test['connectedCells'], mat_info['verticesInfo']['connectedCells'][0][0])
-
-    def test_calculate_vertices(self):
-        """
-        Test the calculate_vertices function.
-        :return:
-        """
-        # Load data
-        _, _, mat_info = load_data('calculate_vertices_wingdisc.mat')
-
-        # Load data
-        labelled_img = mat_info['labelledImg']
-        img_neighbours_all = [np.concatenate(neighbours[0]) for neighbours in mat_info['neighbours']]
-        ratio = 2
-
-        img_neighbours_all.insert(0, None)
-
-        # Test if initialize geometry function does not change anything
-        vertices_info_test = calculate_vertices(labelled_img, img_neighbours_all, ratio)
-
-        # Load expected
-        _, _, mat_info_expected = load_data('calculate_vertices_wingdisc_expected.mat')
-
-        # Assert
-        assert_matrix(vertices_info_test['connectedCells'], mat_info_expected['verticesInfo']['connectedCells'][0][0])
-
     def test_get_four_fold_vertices(self):
         """
         Test the get_four_fold_vertices function.
@@ -453,11 +360,11 @@ def test_process_image(self):
         """
         # Process image
         file_name = 'LblImg_imageSequence.mat'
-        test_dir = 'Tests/data/%s' % file_name
+        test_dir = 'Tests/Tests_data/%s' % file_name
         if exists(test_dir):
             _, imgStackLabelled_test = process_image(test_dir)
         else:
-            _, imgStackLabelled_test = process_image('data/%s' % file_name)
+            _, imgStackLabelled_test = process_image('Tests_data/%s' % file_name)
 
         # Load expected
         _, _, mat_info_expected = load_data('process_image_wingdisc_expected.mat')
@@ -476,11 +383,11 @@ def test_initialize_voronoi_from_time_image(self):
         # Test if initialize geometry function does not change anything
         vModel_test = VertexModelVoronoiFromTimeImage(set_test)
         file_name = 'voronoi_40cells.pkl'
-        test_dir = TEST_DIRECTORY + '/Tests/data/%s' % file_name
+        test_dir = TEST_DIRECTORY + '/Tests/Tests_data/%s' % file_name
         if exists(test_dir):
             vModel_test.set.initial_filename_state = test_dir
         else:
-            vModel_test.set.initial_filename_state = 'data/%s' % file_name
+            vModel_test.set.initial_filename_state = 'Tests_data/%s' % file_name
 
         vModel_test.initialize()
 
@@ -496,3 +403,63 @@ def test_initialize_voronoi_from_time_image(self):
         assert_array1D(g_test, mat_info['g'])
         assert_matrix(K_test, mat_info['K'])
 
+    def test_weird_bug_should_not_happen(self):
+        """
+        Test for a weird bug that should not happen.
+        :return:
+        """
+        # Load data
+        vModel_test = load_data('vertices_going_wild.pkl')
+
+        # Run for 20 iterations. dt should not decrease to 1e-1
+        vModel_test.set.tend = vModel_test.t + 20 * vModel_test.set.dt0
+
+        # Update tolerance
+        vModel_test.set.dt_tolerance = 0.25
+
+        # Run the model
+        vModel_test.iterate_over_time()
+
+        # Check if it did not converge
+        self.assertFalse(vModel_test.didNotConverge)
+
+    def test_vertices_shouldnt_be_going_wild(self):
+        """
+        Test for another weird bug that should not happen.
+        :return:
+        """
+        # Load data
+        vModel_test = load_data('vertices_going_wild_2.pkl')
+
+        # Run for 10 iterations. dt should not decrease to 1e-1
+        vModel_test.set.tend = vModel_test.t + 20 * vModel_test.set.dt0
+
+        # Update tolerance
+        vModel_test.set.dt_tolerance = 0.25
+
+        # Run the model
+        vModel_test.iterate_over_time()
+
+        # Check if it did not converge
+        self.assertFalse(vModel_test.didNotConverge)
+
+    def test_vertices_shouldnt_be_going_wild_3(self):
+        """
+        Test for another weird bug that should not happen.
+        :return:
+        """
+        # Load data
+        vModel_test = load_data('vertices_going_wild_3.pkl')
+
+        # Run for 10 iterations. dt should not decrease to 1e-1
+        vModel_test.set.tend = vModel_test.t + 20 * vModel_test.set.dt0
+
+        # Update tolerance
+        vModel_test.set.dt_tolerance = 0.25
+
+        # Run the model
+        vModel_test.iterate_over_time()
+
+        # Check if it did not converge
+        self.assertFalse(vModel_test.didNotConverge)
+
diff --git a/Tests/tests.py b/Tests/tests.py
index bc6b2f8..656c3b2 100644
--- a/Tests/tests.py
+++ b/Tests/tests.py
@@ -1,36 +1,59 @@
+import logging
+import os
 import unittest
+import warnings
+
 import scipy.io
 import numpy as np
 from os.path import exists, abspath
 
+from src.pyVertexModel.algorithm.vertexModelVoronoiFromTimeImage import VertexModelVoronoiFromTimeImage
 from src.pyVertexModel.geometry.geo import Geo
 from src.pyVertexModel.parameters.set import Set
-from src.pyVertexModel.Kg import kg_functions
+from src.pyVertexModel.util.utils import load_state
 
 def load_data(file_name, return_geo=True):
-    test_dir = abspath('Tests/data/%s' % file_name)
-    if exists(test_dir):
-        mat_info = scipy.io.loadmat(test_dir)
-    else:
-        mat_info = scipy.io.loadmat('data/%s' % file_name)
+    test_dir = abspath('Tests/Tests_data/%s' % file_name)
+    if file_name.endswith('.mat'):
+        if exists(test_dir):
+            mat_info = scipy.io.loadmat(test_dir)
+        else:
+            mat_info = scipy.io.loadmat('Tests_data/%s' % file_name)
 
-    if return_geo:
-        if 'Geo' in mat_info.keys():
-            geo_test = Geo(mat_info['Geo'])
+        if return_geo:
+            if 'Geo' in mat_info.keys():
+                geo_test = Geo(mat_info['Geo'])
+            else:
+                geo_test = None
+
+            if 'Set' in mat_info.keys():
+                set_test = Set(mat_info['Set'])
+                if set_test.OutputFolder.__eq__(b'') or set_test.OutputFolder is None:
+                    set_test.OutputFolder = '../Result/Test'
+            else:
+                set_test = None
         else:
             geo_test = None
+            set_test = None
 
-        if 'Set' in mat_info.keys():
-            set_test = Set(mat_info['Set'])
-            if set_test.OutputFolder.__eq__(b'') or set_test.OutputFolder is None:
-                set_test.OutputFolder = '../Result/Test'
+        return geo_test, set_test, mat_info
+    elif file_name.endswith('.pkl'):
+        v_model = VertexModelVoronoiFromTimeImage(create_output_folder=False)
+        if exists(test_dir):
+            load_state(v_model, test_dir)
         else:
-            set_test = None
+            load_state(v_model, 'Tests_data/%s' % file_name)
+
+        # Set parameters to avoid file output during tests
+        v_model.set.OutputFolder = None
+        v_model.set.export_images = False
+        v_model.set.VTK = False
+
+        return v_model
     else:
-        geo_test = None
-        set_test = None
+        raise FileNotFoundError('File %s not found' % file_name)
+
 
-    return geo_test, set_test, mat_info
 
 
 def assert_matrix(k_expected, k):
diff --git a/Tests_data/Geo_3x3_dofs_expected.mat b/Tests_data/Geo_3x3_dofs_expected.mat
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diff --git a/Tests_data/check_ys_and_faces_have_not_changed_wingdisc.mat b/Tests_data/check_ys_and_faces_have_not_changed_wingdisc.mat
new file mode 100644
index 0000000..a183e1c
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diff --git a/Tests_data/create_tetrahedra_wingdisc.mat b/Tests_data/create_tetrahedra_wingdisc.mat
new file mode 100644
index 0000000..e008e42
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diff --git a/Tests_data/delaunay_compute_entities_expected.mat b/Tests_data/delaunay_compute_entities_expected.mat
new file mode 100644
index 0000000..adc16d1
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diff --git a/Tests_data/delaunay_compute_entities_input.mat b/Tests_data/delaunay_compute_entities_input.mat
new file mode 100644
index 0000000..8e89eaa
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diff --git a/Tests_data/delaunay_input_expected.mat b/Tests_data/delaunay_input_expected.mat
new file mode 100644
index 0000000..13b9e4c
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diff --git a/Tests_data/delaunay_output_cyst.mat b/Tests_data/delaunay_output_cyst.mat
new file mode 100644
index 0000000..821788d
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diff --git a/Tests_data/flipNM_cyst.mat b/Tests_data/flipNM_cyst.mat
new file mode 100644
index 0000000..157ff9f
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diff --git a/Tests_data/flipNM_recursive_cyst.mat b/Tests_data/flipNM_recursive_cyst.mat
new file mode 100644
index 0000000..a913e18
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diff --git a/Tests_data/flipNM_recursive_cyst_expected.mat b/Tests_data/flipNM_recursive_cyst_expected.mat
new file mode 100644
index 0000000..1b32d31
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diff --git a/Tests_data/generate_first_ghost_nodes_expected.mat b/Tests_data/generate_first_ghost_nodes_expected.mat
new file mode 100644
index 0000000..2443999
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diff --git a/Tests_data/geo_cyst_expected_extrapolatedYs.mat b/Tests_data/geo_cyst_expected_extrapolatedYs.mat
new file mode 100644
index 0000000..c161c19
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diff --git a/Tests_data/get_dofs_remodel.mat b/Tests_data/get_dofs_remodel.mat
new file mode 100644
index 0000000..e4ad92a
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diff --git a/Tests_data/get_four_fold_vertices_wingdisc.mat b/Tests_data/get_four_fold_vertices_wingdisc.mat
new file mode 100644
index 0000000..9e425d5
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diff --git a/Tests_data/get_node_neighbours_per_domain_wingdisc.mat b/Tests_data/get_node_neighbours_per_domain_wingdisc.mat
new file mode 100644
index 0000000..2c56fb6
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diff --git a/Tests_data/initialize_cells_cyst_expected.mat b/Tests_data/initialize_cells_cyst_expected.mat
new file mode 100644
index 0000000..0c8bbd3
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diff --git a/Tests_data/initialize_voronoi_wingdisc.mat b/Tests_data/initialize_voronoi_wingdisc.mat
new file mode 100644
index 0000000..83eee65
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diff --git a/Tests_data/kK_test.mat b/Tests_data/kK_test.mat
new file mode 100644
index 0000000..3401560
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diff --git a/Tests_data/line_search_cyst.mat b/Tests_data/line_search_cyst.mat
new file mode 100644
index 0000000..febeea9
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diff --git a/Tests_data/obtain_x_and_twg_wingdisc.mat b/Tests_data/obtain_x_and_twg_wingdisc.mat
new file mode 100644
index 0000000..ffc4951
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diff --git a/Tests_data/populate_vertices_info_wingdisc.mat b/Tests_data/populate_vertices_info_wingdisc.mat
new file mode 100644
index 0000000..48d032f
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diff --git a/Tests_data/post_flip_wingdisc.mat b/Tests_data/post_flip_wingdisc.mat
new file mode 100644
index 0000000..b038804
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diff --git a/Tests_data/post_flip_wingdisc_2.mat b/Tests_data/post_flip_wingdisc_2.mat
new file mode 100644
index 0000000..078b96b
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diff --git a/Tests_data/post_flip_wingdisc_2_expected.mat b/Tests_data/post_flip_wingdisc_2_expected.mat
new file mode 100644
index 0000000..30cd404
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diff --git a/Tests_data/post_flip_wingdisc_expected.mat b/Tests_data/post_flip_wingdisc_expected.mat
new file mode 100644
index 0000000..18221b4
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diff --git a/Tests_data/process_image_wingdisc_expected.mat b/Tests_data/process_image_wingdisc_expected.mat
new file mode 100644
index 0000000..f919853
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diff --git a/Tests_data/rebuild_stretch_3x3_expected.mat b/Tests_data/rebuild_stretch_3x3_expected.mat
new file mode 100644
index 0000000..774a663
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diff --git a/Tests_data/rebuild_wingdisc_expected.mat b/Tests_data/rebuild_wingdisc_expected.mat
new file mode 100644
index 0000000..d3aabb1
Binary files /dev/null and b/Tests_data/rebuild_wingdisc_expected.mat differ
diff --git a/Tests_data/remodelling_intercalating_cells_wingdisc.mat b/Tests_data/remodelling_intercalating_cells_wingdisc.mat
new file mode 100644
index 0000000..62caf47
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diff --git a/Tests_data/remodelling_intercalating_cells_wingdisc_expected.mat b/Tests_data/remodelling_intercalating_cells_wingdisc_expected.mat
new file mode 100644
index 0000000..871cd8e
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diff --git a/Tests_data/remove_tetrahedra_wingdisc.mat b/Tests_data/remove_tetrahedra_wingdisc.mat
new file mode 100644
index 0000000..74dd62f
Binary files /dev/null and b/Tests_data/remove_tetrahedra_wingdisc.mat differ
diff --git a/Tests_data/seed_with_bbox_expected.mat b/Tests_data/seed_with_bbox_expected.mat
new file mode 100644
index 0000000..197709f
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diff --git a/Tests_data/seed_with_bbox_input.mat b/Tests_data/seed_with_bbox_input.mat
new file mode 100644
index 0000000..4e7c12c
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diff --git a/Tests_data/solve_remodelling_step_wingdisc.mat b/Tests_data/solve_remodelling_step_wingdisc.mat
new file mode 100644
index 0000000..e7bc636
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diff --git a/Tests_data/test_gkDet.mat b/Tests_data/test_gkDet.mat
new file mode 100644
index 0000000..8367fff
Binary files /dev/null and b/Tests_data/test_gkDet.mat differ
diff --git a/Tests_data/vertices_going_wild.pkl b/Tests_data/vertices_going_wild.pkl
new file mode 100644
index 0000000..bdf9f86
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diff --git a/Tests_data/vertices_going_wild_2.pkl b/Tests_data/vertices_going_wild_2.pkl
new file mode 100644
index 0000000..17715ed
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diff --git a/Tests_data/vertices_going_wild_3.pkl b/Tests_data/vertices_going_wild_3.pkl
new file mode 100644
index 0000000..fd0cf75
Binary files /dev/null and b/Tests_data/vertices_going_wild_3.pkl differ
diff --git a/Tests_data/voronoi_40cells.pkl b/Tests_data/voronoi_40cells.pkl
new file mode 100644
index 0000000..885360a
Binary files /dev/null and b/Tests_data/voronoi_40cells.pkl differ
diff --git a/Tests_data/wing_disc_110.mat b/Tests_data/wing_disc_110.mat
new file mode 100644
index 0000000..16fd31d
Binary files /dev/null and b/Tests_data/wing_disc_110.mat differ
diff --git a/Tests_data/wing_disc_150.mat b/Tests_data/wing_disc_150.mat
new file mode 100644
index 0000000..a91d303
Binary files /dev/null and b/Tests_data/wing_disc_150.mat differ
diff --git a/src/pyVertexModel/algorithm/vertexModel.py b/src/pyVertexModel/algorithm/vertexModel.py
index 0eb1a43..be339f3 100644
--- a/src/pyVertexModel/algorithm/vertexModel.py
+++ b/src/pyVertexModel/algorithm/vertexModel.py
@@ -429,9 +429,10 @@ def iterate_over_time(self):
         updating measures, and checking for convergence.
         :return:
         """
-        temp_dir = os.path.join(self.set.OutputFolder, 'images')
-        if not os.path.exists(temp_dir):
-            os.makedirs(temp_dir)
+        if self.set.OutputFolder is not None:
+            temp_dir = os.path.join(self.set.OutputFolder, 'images')
+            if not os.path.exists(temp_dir):
+                os.makedirs(temp_dir)
 
         if self.set.Substrate == 1:
             self.Dofs.GetDOFsSubstrate(self.geo, self.set)
@@ -533,7 +534,7 @@ def iteration_did_not_converged(self):
             self.set.nu = 10 * self.set.nu0
         else:
             if (self.set.iter >= self.set.MaxIter and
-                    (self.set.dt / self.set.dt0) > 1e-6):
+                    (self.set.dt / self.set.dt0) > self.set.dt_tolerance):
                 self.set.MaxIter = self.set.MaxIter0
                 self.set.nu = self.set.nu0
                 self.set.dt = self.set.dt / 2
@@ -615,16 +616,17 @@ def save_v_model_state(self, file_name=None):
         :param file_name:
         :return:
         """
-        # Create VTK files for the current state
-        self.geo.create_vtk_cell(self.set, self.numStep, 'Edges')
-        self.geo.create_vtk_cell(self.set, self.numStep, 'Cells')
-        temp_dir = os.path.join(self.set.OutputFolder, 'images')
-        screenshot(self, temp_dir)
-        # Save Data of the current step
-        if file_name is None:
-            save_state(self, os.path.join(self.set.OutputFolder, 'data_step_' + str(self.numStep) + '.pkl'))
-        else:
-            save_state(self, os.path.join(self.set.OutputFolder, file_name + '.pkl'))
+        if self.set.OutputFolder is not None:
+            # Create VTK files for the current state
+            self.geo.create_vtk_cell(self.set, self.numStep, 'Edges')
+            self.geo.create_vtk_cell(self.set, self.numStep, 'Cells')
+            temp_dir = os.path.join(self.set.OutputFolder, 'images')
+            screenshot(self, temp_dir)
+            # Save Data of the current step
+            if file_name is None:
+                save_state(self, os.path.join(self.set.OutputFolder, 'data_step_' + str(self.numStep) + '.pkl'))
+            else:
+                save_state(self, os.path.join(self.set.OutputFolder, file_name + '.pkl'))
 
     def reset_noisy_parameters(self):
         """
diff --git a/src/pyVertexModel/parameters/set.py b/src/pyVertexModel/parameters/set.py
index 9062c11..560dd39 100644
--- a/src/pyVertexModel/parameters/set.py
+++ b/src/pyVertexModel/parameters/set.py
@@ -13,6 +13,7 @@
 
 class Set:
     def __init__(self, mat_file=None):
+        self.dt_tolerance = 1e-6
         self.min_3d_neighbours = None
         self.periodic_boundaries = True
         self.frozen_face_centres = False
@@ -179,9 +180,8 @@ def check_for_non_used_parameters(self):
         if not self.brownian_motion:
             self.brownian_motion_scale = 0
 
-        if self.implicit_method is False:
+        if not self.implicit_method:
             self.tol = self.nu
-            self.tol0 = self.nu/20
 
         if self.Remodelling:
             self.RemodelStiffness = 0.9
@@ -309,7 +309,7 @@ def bubbles(self):
         self.check_for_non_used_parameters()
 
     def cyst(self):
-        mat_info = scipy.io.loadmat(os.path.join(PROJECT_DIRECTORY, 'Tests/data/Geo_var_cyst.mat'))
+        mat_info = scipy.io.loadmat(os.path.join(PROJECT_DIRECTORY, 'Tests_data/Geo_var_cyst.mat'))
         self.read_mat_file(mat_info['Set'])
         self.InputGeo = 'Bubbles_Cyst'
         self.CellHeight = 15
diff --git a/uv.lock b/uv.lock
index db6673d..2a26a38 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1093,6 +1093,7 @@ dependencies = [
     { name = "scikit-learn", version = "1.8.0", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.11'" },
     { name = "scipy", version = "1.15.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
     { name = "scipy", version = "1.17.0", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.11'" },
+    { name = "seaborn" },
     { name = "vtk" },
 ]
 
@@ -1108,6 +1109,7 @@ requires-dist = [
     { name = "scikit-image" },
     { name = "scikit-learn" },
     { name = "scipy" },
+    { name = "seaborn" },
     { name = "vtk" },
 ]
 
@@ -1513,6 +1515,22 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/a3/bb/bbae36d06c0fd670e8373da67096cd57058b57c9bad7d92969b5e3b730af/scooby-0.11.0-py3-none-any.whl", hash = "sha256:a79663d1a7711eb104e4b2935988ea1ed5f7be6b7288fad23b4fba7462832f9d", size = 19877, upload-time = "2025-11-01T19:22:53.046Z" },
 ]
 
+[[package]]
+name = "seaborn"
+version = "0.13.2"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "matplotlib" },
+    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
+    { name = "numpy", version = "2.4.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.11'" },
+    { name = "pandas", version = "2.3.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
+    { name = "pandas", version = "3.0.0", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.11'" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/86/59/a451d7420a77ab0b98f7affa3a1d78a313d2f7281a57afb1a34bae8ab412/seaborn-0.13.2.tar.gz", hash = "sha256:93e60a40988f4d65e9f4885df477e2fdaff6b73a9ded434c1ab356dd57eefff7", size = 1457696, upload-time = "2024-01-25T13:21:52.551Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/83/11/00d3c3dfc25ad54e731d91449895a79e4bf2384dc3ac01809010ba88f6d5/seaborn-0.13.2-py3-none-any.whl", hash = "sha256:636f8336facf092165e27924f223d3c62ca560b1f2bb5dff7ab7fad265361987", size = 294914, upload-time = "2024-01-25T13:21:49.598Z" },
+]
+
 [[package]]
 name = "six"
 version = "1.17.0"