I was on the fungal level (floor 5), and had just cast the Rune of Exploding (Promethean level 2). A mushy stepped on it, and the resulting explosion killed the Mushy and a Unhealthful Golem, giving me the XP needed to level up. Level-up window pops up as normal, and I selected Psychic Vampirism (Vamp level 4) which I had never taken before on any other character. After clicking on the skill selection, I clicked the box in the corner of the level-up screen to go back to the game as I always do. At that point the game froze for several seconds, and then crashed to the desktop. I was playing on Permadeath, but it didn't nuke my save - not only do I show a normal save that depicts my character on floor 4, there's also an autosave above it on the list that shows the same character, but strangely enough it shows the character on floor 3, which I did not set foot on during this play session. What's more, there was _not_ an autosave (of any level) on the load screen when I went to start play today. Mac OSX 10.6.8, using latest Steam version. I did have a mod installed, but it (Interior Dredmorating) does not have any skills and doesn't in any way alter the normal performance of Vampirism. The room this happened in was not one of my modded rooms, nor can I think of anything else in the mod that could be causing this crash.
Since your save is still there, can you verify whether it crashes again, or it was just a random crash? If so, please upload it, it will help a lot.
