Any news on this? This issue is making me lost many hours redoing things. It makes the engine very unreliable for me. Data lost is, in my opinion, one of the worst errors that can happen.
One thing I noticed is that sometimes the issue happens when I duplicate an actor. For example, I have an actor X with a value Y on some property. I alt+drag the actor to create a copy of the actor. The new actor is created, and it is almost perfect, BUT the property doesn’t have the value Y. Instead, the property of the new actor is empty (the original actor remains with the value Y).