Darucas: ddraw.dll isn't of much help to me, as it seems to mess with the launcher advanced settings (it always reverts to default setting once I start the game). I put it in the main directory. However, as with quite a lot of other games under 8.1, the first solution (using Application Comp. Toolkit) works well as long as I disable light mapping, as you said. Otherwise, the framerate is unstable. Still, the interface flickers a lot.

Microsoft could sure do a better job, but overall I don't find 8.1 more or less of an issue than 7, although fixes and issues are different (less crashes, better colours, performance problems though). BUT, Blood 2... and generally speaking the first Lithtech games (before AvP2)... they really need a 100% efficient way to be launched windowed or something (DxWnd? DXGL?? Wine? Tried all of them a few months ago, no luck, but they may have been updated). And Blood 2 is the worst in my experience.