We have our remote PCs connected to a large monitor set at 1920x1080 which matches the resolution on the laptops we use to connect with. However, after a couple of weeks the screen resolution on the host computer changed itself to 1024x768. 
This makes it so we cannot see everything we need to with the applications we are using on the host computer. When we try to select a different screen resolution and click "Keep new settings" the resolution stays at 1024x768. The various settings within GoToMyPC do not have an affect on the screen resolution. Only on the size of the viewing window.
Restarting the host PC and restarting the GoToMyPC session does not have any effect either.