Looked here: https://steamcommunity.com/app/427700/discussions/0/1480982971155489161/

It was of no help.

My copy of GOG Zwei isn't recognizing my 2070. The option to select video cards is grayed out. Additionally, when I select Start Game, the game gives me just a hint of a title bar in the upper-left corner of the screen and I can't see any of the window at all.

I can tell that it's running because my laptop fan kicks into high gear, but I can't see anything at all.

Any help appreciated.

Running both ZWEI2P.exe and ZWEI2PDX9.exe, same result.

Thanks!

I really wish I could help. My GTX970 is recognized. Maybe it has something to do with the Intel integrated graphics since it's a laptop? I would contact gog support they might be able to provide better solutions.

I remember having issues like that fairly regularly when I used to use a gaming laptop. One of the reasons I'm glad I use the desktop now.

Hopefully, more helpfully...

First: I'm assuming the screen scaling is too large, if this is not the case ignore the below fix:
Try right clicking on both ZWEI2P.exe, ZWEI2PDX9.exe. Properties ->Compatibility->Change high DPI settings
and try checking both boxes. Make sure override is performed with "Application".

Second: Have you tried forcing config.exe, ZWEI2P.exe, ZWEI2PDX9.exe to use The nvidia option through the Nvidia Control Panels: Manage 3D settings?

Could also try temporarily setting the global settings to use the Nvidia card and see if that does it. (Don't set it permanently though as it will drastically decrease battery life)

If that doesn't work you could try using the dgVoodoo2 wrapper.
http://dege.freeweb.hu/dgVoodoo2/dgVoodoo2/
or
https://github.com/dege-diosg/dgVoodoo2/releases

You'd need to put dgVoodooCpl.exe, dgVoodoo.conf from the zip into the Zwei II folder. Then add the 4 files from the MS\x86 in the zip as well. *Note: If you need to uninstall dgVoodoo2 just delete these files.

Run dgVoodooCpl.exe, allow it to run when WIndows complains. You should then be able to select your adapter in the "Rendering" area. Hopefully (May need to try and force it with the Nvidia control panel). Regardless, It will override what graphics adapter Zwei runs, as you'll be able to see in the watermark (You can turn that off in the DirectX tab).