Seeing all the posts I think the problem is in the saved games, not in the hardware config or the installation. I'll try replaying the level exactly as the CNET walkthrough discribes it; if that works I'll send the "defective" save-game to Lucasarts.
It's a million to one chance, but it might just work... (oops, no Pratchett forum)
http://www.indyjones.net/forums/smile.gif)
(PS: this might take a while; I don't have much time to play... but I'll post the results when I've finished)
[This message has been edited by Foul Ole Ron (edited December 12, 1999).]