If you're having a problem starting the game after having changed the resolution to the maximum supported then this may help you.

It seems that on some graphics cards (mine is a GTX-675M) the game struggles to initialise D3D when the resolution is set too high. The game will then fail to ever start again.

The solution for me was to reset the resolution back to 800x600 in the Resolution.cfg file in the games directory with the following line:

800 600 0

With panel scaling on my laptop this makes the game look how I remembered it on my XBox so my nostalgia is more than satisfied with this setting :)

I had this issue after running it fine for the first time and changing the resolution to 1280 x 1024. It wouldn't start with the D3D error.

However, after looking in the game's root folder, I came across a GOG icon'd file called "settings.exe" which allowed me to choose a resolution (in my case 1600 x 900) and launch the game in full and widescreen without problems.

Hurrah!

Are you talking about first FSW or Ten Hammers?
I Install Ten Hammers and I get appcrash everytime I try to run it.
There are settings.exe but all they allow to change is language of the game. Never mind. I solved the problem.

No, that was just for the normal FSW. I haven't tried "Ten Hammers" yet. In case I have the same problem when I do, what was the method you used to solve the issue?