Problems with the Gog.com version

[solidseverus]

I bought the gog.com version and the game is stuck in a small resolution window. I tried to run the winsetup.exe in the game's installation folder but it gave me the following error. "Error: unable to launch 'Shivah.exe'. Make sure that the file is in the same directory as this Setup program." The game is not unplayable like it is but I'd much rather have it run fullscreen. If anyone knows how to fix this I'd be very appreciative. I'm running Windows 8.1 Enterprise 32-bit.

Edit: Just to be clear, I've already tried forcing fullscreen in the windows options and it still didn't work

[jimrh1969]

I have the same problem 

[DaveGilbert]

Huh! I wonder if this is something specific to the way GOG organized the files. Check your PM. I'd like to test something.

[WadgetEyeGamesIsCool]

Try to open winsetup.exe by right clicking a choosing run as admin or run in compatibility. You'll then get a window and then uncheck the box which says Run in a Window instead of Full-Screen. It worked for me.
Hope this helps you!