The thing with the masks..

[Gustavo Bermudas]

This used to happen to me all the time since version 8, and I found out if you have a custom shape, that is tracked, then you have to be very careful not to accidentally add additional points when trying to move the shape otherwise Resolve will crash

[Laco Gaal]

I had this in V8. Had a 30 seconds ad, during the root part it crashed every 5 minutes.
If it helps, I can import that project again, and send a crash log.