This is an incomplete draft of my 'Mountainbleed' build that involves carving giant letters in a cliff. Whenever I boot up stonesense and scroll to certain layers, it crashes all the way to desktop. It seems like z=-1, z=-4 and z=23(?) always do it. Two of those layers have a ton of rocks but why 23?? That's the nondescript middle of a cliff.

Any ideas what's causing this would be very welcome. Someone requested I upload it here for them to see.
No mods running save DFHack.