That's stored in your profile settings. Just open your profiles and set your default resolution and it should save it. I set the resolution to 1920x1080 for all my profiles (instead of , which should use whatever the default setting is), and it still won't set the resolution properly. I have to manually switch profile for it to set properly (i.e. 'End', 'Home' to select next/previous profile). Then I can enter with the right resolution, but if I esc-Q, the resolution in the 'Resolution' menu sets itself back to 1600x1024. Hmm, I just checked the register, and HKEY_CURRENT_USER\Software\Continuum\State\ResolutionX / Y seem to define the current resolution used. But in my case, it seems to be correctly changing. It's just the selected resolution switches back to 1600x1024... hmm... It happens both with windowed and fullscreen. I have 2 monitors, but my second one is 1440x900, so it's probably unrelated? It's weird, anyway.