Monsters don't appear to stop on delayed path nodes.
In software mode, looking straigt up or down causes a graphical error.
In GL mode, the way lighting works outdoors (or perhaps places with Line_horizon) is just a bit odd. WARNING: these are 1280*960! Sorry these are so big, it's hard to see it at 640*400 and they came out larger than 1024*768 for some reason:
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Dead body sprites go a bit below the floor:
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And last but not least, as I recently found out above, screenshots taken in 1024*768 come out in 1280*960.
I might've found some other of these small things but if I did I surely don't remember.