I installed RetroPie on my raspberry pi and it worked great, save for roms loading in 480x640 resolution. I tried to go into es_systems.cfg through WinSCP to edit it and fix the resolution problem, but every time I make an edit and save it saves a blank file. I've also tried deleting the original and moving a copy over to the .emulationstation folder, and it saves the copy as blank too. Any ideas?