Accidentally posted this somewhere else, not knowing of this thread. Reposting:
Running 1.2 US on XP, with the full installer and the three extra fixes, and nothing else.
In a new game, in Arroyo, Entering my Pipboy Automap screen and selecting any map generates a new option called "Desert", though selecting it shows a blank screen. Entering a new area (and other triggers I haven't been able to determine) creates more "Desert" options, and selecting the third "Desert" causes a fatal crash, presumably because it fills a slot that no Arroyo map exists in.
Attacking a Golden Gecko with a (Combat) Knife in the Toxic Caves (and possibly elsewhere) causes a fatal crash.
Fatal crash in Random Encounter Robber Cave. Not sure of cause.
Saving on a Kaga encounter map and loading causes the encounter to restart, even if finished. Any XP gained (e.g. through dissuading him from killing the player) can be collected repeatedly.
EDIT: Fatal crash when quicksaving outside a cave encounter. Save corrupted.
After all this development, is this honestly still so unstable? Does this happen to everyone else, or should I try a reinstall?