Every time I try to load up M&M 6, 7 or 8 I just get a grey screen followed by the message DDraw->SetDisplayMode() failed. I hvae tried the GrayFace patches for all three of them but get the same result. I was able to get 7 & 8 to boot up with dgVoodoo but the mouse does not work properly. I can't select things normally, I can only select thing if I have the mouse courser about 7 to 10 cm's to the left of the object I want to select, this happens in both the menus and the game itself (sometimes its even further in the game its self). I can't find anything online about this problem. I am running the game on a new Windows 10 machine, but I have already installed all the regular updates and fixes GOG often recommends.

are you running dual monitors?

No just a standard 1080p monitor on 1920x1080 through a HDMI.

Did you change resolution in dgVoodoo DirectX tab?

Due to issues with other games I leave the scaling mode unspecified and the resolution unforced. I do though use the other greater (free to configure) 3Dfx card option as I like to mess around with things when possible (but I do only make major changes when I have the things working in the first place).

I had a similar problem with QfG5 from GoG when changing resolution in dgVoodoo. It works fine for MM games though (except Arcomage game but it's still playable) but I have original CD versions and Windows 7.