But now I have to:
1. Open up the game app.
2. Change from full screen mode to windowed mode.
3. Quit the game app.
4. Edit the D3prefs.txt file to change the windowed mode resolution to what I want it to be. Then save and quit this.
5. Open up the game app again
Only then I can play. Why am I forced to do this everytime I want to play Diablo 3.
And btw you can't also change in game the windowed resolution for Starcraft 2 WoL.