Hey! Sorry to hear that, never something we want to hear.
Mind telling us what OS you're using?
-ATKMTN
I had closed and relaunched to same results that same day. Just launched the game again to see if I can get any extra details on the issue.. and it launched just fine.
I can't alt tab out and back in, however, as the game doesn't return to full screen and doesn't display itself: I get a window border in top left of my monitor around other things already on my screen. Audio still functional, however.