Minor issues reported during testing hackathon, which can be fixed with checklist updates.
1. `draw a segmentation mask in different image slices in a single render window, leaving empty slices in between` -> `In the 3D render window black contours are drawn around the green interpolated surface.` -> Actually contours are drawn in red.
2. `Use “Undo” / “Redo” buttons from the MITK tool bar` -> `The interpolation is updated accordingly.` -> Interpolation is only updated when reinit interpolation button is clicked.
3. `select “3-Dimensional” as interpolation mode` -> `The interpolated contour is rendered again.` -> Interpolation is only updated when reinit interpolation button is clicked.
4. Above test cases are reported because there was no number to test case. Test cases needs numbering