Been out of the loop for a long time. Just installed 2.31 and a bunch of my old project files won't load. These projects go back to 2018 and earlier, so can't remember which version they were created with. Most crash when 0% is parsed on loading.
I could open these in 32bit Magic. This project 'disappeared' Magic in 64bit for me also. Not much interesting in the Event log but the crash was in there. I couldn't see anything obvious that would cause a crash but didn't go through everything.
I found a workaround. I copied the files to my desktop, where they were able to open. Interestingly, copying the original enclosing folder to the desktop did not work, as they refused to open from it.
Tried saving them (the ones individually copied to desktop) to another folder, and they would open from their new location as well.
All very strange, but at least the work is recoverable. That's all that matters.