I am currently playing Codename Outbreak from GOG on Win7. By default, it has issues with texture transparency which make it hideous to play. With dgVoodoo 2.53, the problem is gone and it is enjoyable to play. However, the intro movies only play the sound on a black screen and video sequences embedded into the GUI (as in, the weapon previews in the loadout menu) do not display at all. All those videos are AVIs, codec info from MPC: Video: IV50 640x480 25fps 1755kbps [V: indeo5, yuv410p, 640x480, 1755 kb/s]. MPC displays the videos properly.
Any help is appreciated.