Make sure that it's running in a resolution your monitor can display. You can modify the settings by going to the game folder and running the nglide_config application.
The only way I could get it to play the opening video is by having WIndows apply compatibility mode. You can enable compatibility mode by right clicking the Wiz8 application, going to the Compatibility tab and running the compatibility trouble shooter. Mine runs it for XP SP3.
To be fair, even having it in a compatible resolution doesn't seem to help once it starts going wrong. I had it set at a variety of correct resolutions and always got a video error when starting up.
It seems to be down to an interaction between setting graphics with 3Dsetup.exe or 3Dvideo.cfg and
setting them with nglide_config.exe. In my experience, doing anything with the first two (which are linked as the latter is the config file that stores the settings made with the exe) can bring up problems when you then make other settings with nglide. With my current fresh installation, the supposed settings in 3Dvideo.cfg are all default stuff yet the game is actually running in 4K thanks to nglide.
For anyone else with this problem, if that doesn't help, try the widescreen patch. The UI gets stretched and that really bothers me but others might not mind as much. It did get the game to work when all else failed, though, even when it was giving me BS about "unsupported resolutions".