As far as I remember, the second monitor should be disabled (WinKey + P combination). Try do disable 1 monitor and go with another. Meanwhile I'll think of possible solutions.
Tried it just now,i've dissable and tried both moniter the result still the same. The moniters i'm using have different resolution.
The error keep popping out "Coun't Rasterize API"
Rasterizing API is graphics related. So I would only blame the videocard or videocard device manager settings.
The things is dgVoodoo is supposed to eliminate ALL of those problems since it's a wrapper program. Especially if it's paired with the Resolution patch. Is your "Disable and passthru to real DirectX" option checked? Because it shouldn't be.
Ok, let's try once again.
1. Install the resolution patch over 1.50q (Winter Of The Wolf)
2. Install dgVoodoo and use the settings from the screenshots below: