I don't know if there's a possibility to reproduce the failure. I will attach the compromitted file.
I built a score from the cratch. It contained a choral of the 16th century with time signature changes. These changes I didn't like to be seen. So I hid it by hitting key v. Done.
Next was to create the parts. But that got "specific" ... After creating the parts I found in them time signature changes I never created; also key changes I never created. The latter I could delete. But if I tried to delete the superfluous time signature changes, it either happened nothing, or both of time signatures were deleted - even that one what was right.
At least I tried to close the file. The program crashed.
What is corrupt ???
Please, don't build program overloads which lead to dysfunction. That happened with Finale, that happened with Sibelius. No - stop it. Keep the program only for notation. Version 2.x was fine, Version 3.x isn't. That's a GREAT pity.