Weird, I installed the patch (the game was freezing - I had nothing to lose), and also these
Soundblaster Audigy Drivers (
http://fernando.darocha.free.fr/sblive-audigy-xp.zip) for XP.
Some of my save games cause flickering when I load them, but if I load one that is OK and play from there, everything is fine (so far). Certainly no freezes in the last couple of hours.
(Geforce 4 ti4600, ABIT TH7-RAID II, P4 2.0a, WIN XP Pro).