[Squall13]

Has the pixel ratio / overscan / resolution resets been resolved yet in the Gotham builds?

This is a bug both I and doveman2 and others have posted on this see posts #438, #449 and #450.
According to XBMC wiki it should be possible to cut and paste desired guisettings into advancedsettings which should then take precedence. This works for the locale time settings but I have tried this approach with resolution and pixel ratio and other settings with no joy. If the Pi is rebooted I am back to square one (or should I say 0.5 pixel ratio!) with the same problem as you and others.

Thanks