Tuplets seem to be main catalyst for scores having corruptions
Try working around with tuplets on two of the scores I have attached. It mainly happens at random, but in every case that I've looked at the corrupted measures in each file, it has been along the tuplets. It might only occur after Musescore crashes, which might be a different problem, but I've had severe problems trying to use triplets because of this problem. It is fixable by deleting the corrupted measures and recreating the measure, but that can be a problem if you don't remember what the measure looked like. This is my first reported bug, so I apologize if I did anything wrong.