Just had a crash to desktop when I leveled up while in demon form. I levelled on a Djinn Fizz, if that's important. (In the very last room of level 10, after 2 straight hours of clearing. Haven't dared to check where my last autosave was. I might do things to my computer if it's when I came down from 9. Not that I'm bitter or anything. >_> )
It should have created a .dmp file in your game directory, please send that to contact@gaslampgames.com Sorry to hear :/