Manually change resolution / full screen? Can't play!

Hi!

I’m running GSB using crossover games on mac. It was running beautifully until I fiddled with the resolution.
Now GSB started in Full Screen Mode, which I didn’t like. So I disabled it in the options menu. Now the start-Screen is too large to fit on my monitor, I can’t see or access the menu, I can’t play or change any options in-game.

Is there a config-File or similar to change the resolution and/or full-screen-mode?

“my documents/my games/GratuitousSpaceBattles/prefs.ini” holds these settings.