Sintacs_Error: So I'm having same problem as OP. I can find and make the change (fixed, 1920x1080) in tools.exe (running as admin), but it reverts back to 800x600 when the game is launched. If I change it to a selectable option in-game it'll change (though 1280x720 comes out as 800x600, yet 1280x768 seems to be my best option for widescreen as it works properly). I've been able to get some resolutions to stick in tools.exe, but so far any attempts at 16:9 widescreen resolutions default to 800x600.