Well, if it crashes as soon as you click Map Maker, then I'd suggest reinstalling the game:
Save your maps(not WaterMill)and presets(Not preset 1 and 2).
This means, you need to copy your map's folder to somewhere outside the FH folder, it's .map file, and object files it uses. (you don't need to copy those if they are the default ones)
Once you copy all things, uninstall FH, delete the folder, and then reinstall.