I can confirm, that it is indeed working - PNG and TIFF
I did everything the same - except for the bump-thickness. This time I set it to 8 and tried 16, also - working ok.
Guess "100" was a too high value, that causes the crash.
Somewhere, I was suggested to use "100" (saw it on a screenshot over here: http://3d-coat.com/forum/index.php?showtopic=16544 ) - it worked without crashing, back in in beta.12