Here is a fix to get Zero Hour to look nice in Triplehead. I tested it only briefly, but it should universally apply to all ZH maps.
Extract the archive into your Zero Hour program folder. It should create a subfolder structure like this:
..Command & Conquer Generals Zero HourDataINIGameData.ini
If you already have GameData.ini extracted to this folder (for modding or such) it will be overwritten! Backup first!
Triplehead FOV before fix:
Triplehead FOV after fix:
There should be no terrain clipping since I enabled DrawEntireTerrain.
PS-the game looks FANTASTIC on 3 screens.
nice! too bad I don't have the game installed anymore.
wish there was a fix like this for C&C3