Oh my! I haven't been watching my own thread.
Anyway, my findings so far: With some fonts (my own included), this crash happens in a repeatable fashion. With others (the system Courier font, for example), the crash does not happen at all, even under identical circumstances. So what's the difference? My first thought that the game might be using an unusual code for a character somewhere, and the lack of that character in the font is causing the crash. After filling out every reasonable (and many unreasonable) character in my font with something, even if just a scribble, the crash still happens.
But perhaps I've missed some. The main culprit I'm looking at is the item descriptor symbols, since these generally only appear in the screens where it crashes. There's a manual page that describes all the possible descriptors (I'm picking approximate matches from a Unicode chart for some of these):
-Thing- (well crafted)
+Thing+ (finely crafted)
‼Thing‼ (on fire)
xThingx, XThingX, XXThingXX (damaged)
◀Thing▶ (magical) (wait, magic? where?!)
Some of these symbols are mundane, and others are quite esoteric. Does anybody know the exact Unicode numbers for what DF uses for these designations? I must say I don't feel like designing characters for the full 50,000+ Unicode spectrum just in case.