I am currently revisiting SMAX using the GOG version on my Windows 8 laptop. The only problem is the slight one with resolution. Can only use the game's original resolution, which doesn't use the whole screen, or desktop's native resolution (put DirectDraw=0 in the ini file) which almost makes everything too small to see. Got used to it, though. I am also using one of those unofficial patches that fixes some small things and improves the AI a bit, but it worked just great even without.
Still a great game, though the interface is a bit annoying.
Edit: Heh, I had to jinx it by saying that it works fine... Suddenly got the "starting movie crash" bug. Few hours later I tied again and the crash was gone. Oh well, the starting cinematic can be disabled.