After installing 1.66 my game started behaving very oddly, crashing to the desktop at seemingly random locations.

It turned out that all the locations causing these crashes had some form of water present. By disabling "shiny water" in the advanced graphics options the crashes immediately disappeared.

This could be partly due to the latest ATI catalyst 5.6 drivers which were installed several days before I tried the 1.66 patch (although it didn't crash in those few days) so it's probably a combination of the two.

Hopefully we'll have a hotfix soon!

ATI cards have had problems with "shiny water" in the past, although it was solved for quite a few revisions of Catalyst.

I've been running 5.6 since they were released and have only played NWN a few times since but I haven't noticed this particular problem.

I wouldn't be surprised if the 5.6 was causing it. I've never had any problems with Catalyst prior to 5.6 with anything, but I've noticed some unusual things with this latest release.

I'm going back to 5.5 and will probably stay with that driver regardless of new releases. I doubt that ATI is considering their older cards anymore (9800pro) when testing driver releases.