Same here. I tried different things but no joy. I don't think we can do anything about this. It's up to the devs to clean up the mess what they done again. Its a shame they dropped the mac support, we found a way for playing the game on mac and now thats f... up as well. As a lifetime sub-er i'm a bit annoyed.
It does the same to me, but "force quit" solves it. When it crashed press cmd+alt+esc, then the os puts you back to the desktop so you don't have to restart. That way may work for you as well. Now I'm going back to play... oh wait I'm not :/