Corrupt Files - Anyone Else?

Do you get any error messages when running the diagnostics? Have you tried it on another PC? If that's not an option, you could create a new user on your existing machine and see if it still happens. This will help you rule out background processes that might be conflicting. You might also want to try updating the .NET Framework. 

I ran into this years ago. I don't recall the details, but I was able to narrow it down to a  custom state of a particular object. I had copy/pasted a shape from another slide and brought with it some animations or triggers that were not allowed to be part of a state. 

I was able to narrow this down by importing each scene into a separate new file. When only one of them crashed, I started removing one slide at a time until it stopped. You mentioned that it is happening in multiple files so check to see which master layouts, themes, starter slides, templates, etc. are shared between those files.