I've had a curious problem with my mod crashing to desktop in certain situations. I've narrowed it down to RemoveAddedForm().
The bug seems to happen when I have a save with a formlist which my mod has added forms to previously. If I load that save, use RemoveAddedForm() on items in the formlist and then try to reload the save. Then it crashes as it loads.

I'm guessing the game tries to find the forms I removed when I reload.
Don't know if its a known issue. But just thought I would mention it incase someone has the same problem.