Is there any horizontal keystone correction setting on this unit? I found the vertical keystone, but don't see anything else. The studs in my room used for the theater were off center around 6 inches... and the position settings to move the image don't work via HDMI, only PC. I really don't want to put the screen off-center, and I am not sure I have the skills to build a ceiling mount that is off the stud!
The trapezoid is minor if I shoot it towards the center of the room, my wife doesn't even notice it, but it is driving me insane
No horizontal keystone I'm afraid. All you need to do to fix the ceiling mount off-centre to the joists is get a piece of offcut timber (1x4 of suitable length will do), locate the ceiling joists and then screw the offcut to two joists, spanning them. Then screw the ceiling mount to the offcut. Paint the offcut to match the ceiling and you will hardly notice it. If you want a fancier finish, then you could have the offcut bevelled and shaped any way you like.