I guess you learned the hard way about the importance of backups, especially when using a beta product. I know it ****** and I do feel your pain because I've lost stuff too.
But... when I'm working on things now I make VERY frequent backups. This Cursed Rock had almost 100 backups. Platform School currently has 50. It might seem like overkill, but if I lose any work then I only have to go back a couple of hours, rather than start all over again.