It doesn't happen every time, but in several cases, I've gone into my inventory, hit a number (say, 4) so that I could set an item to that key, and had the game immediately CTD.
Win XP SP3
Core 2 Duo 2.66, 4GB ram
ATI HD2600XT mobility / 256mb
(iMac running Win XP via Bootcamp)
(Other bugs I've experienced - crafting menu static noise & list gets stuck when mousing over details on the right; missing save files; and, of course, the usual random CTDs that come with a gamesas game. )