See;
Revealing maps.
Did you try reinstalling Divinity? Zip or otherwise backup your saved games folder to another location first, just in case. Then un-install, re-boot, shut down all non essential programs (especially anti-virus), re-install the game, re-boot, shut down all non essential programs, install the patch, re-boot, shut down all non essential programs, start the game. This procedure is a bit over-cautious, but the best way to avoid install problems.
AFAIK the dawn/dusk effect can be gained/lost by re-installing the game or by installing a patch. Maybe if you reinstall for the first problem, you will end up with it working.
The 'Use AlphaBit' option presumably uses a more compatible, though probably slower, rendering technique. The alpha channel/bit is used in some graphics and 3D rendering as the transparency of that pixel, though I don't know if the meaning is the same in this context.
BTW DATD, I think you are taking your alignment way too seriously. <img src="/ubbthreads/images/graemlins/tongue.gif" alt="" />
