MuseScore 4 (latest release), keeps corrupting my project and crashing when editing them

Consider this a warning to whoever plans on using MuseScore 4. I saved a composition I was working on in ver. 3.6.2 and opened it in ver. 4 and saved it, I also changed one of the tracks to a vst as the original soundfont was garbage. I went to continue to work on it and when it went to open it MuseScore says it's corrupted, but it still opened, so no biggie, I can fix whatever issue the corruption part is, did so and kept working on it. I went to add a tuplet and crash. Open the file again, still says it is corrupted, open it, fix the broken stuff (again), I go to add a time signature change and crash. Open again, same deal, still corrupted and same sorts of issues. I am aware my project uses a lot of quintuplets so I think the issue lies in trying to place them in the part scores (as the places of issue look different in them). Either that or the vst engine is somehow breaking everything. I can't open the file in ver. 3.6.2 either so I can't go back and work on it there. Can someone please help me? I have posted the score in question of this issue, I was also going to post a crash report, but I can't seem to find and crash log in the usual places.