The projector ideally should be mounted between 1/4 and 1/3 back from the closest possible range in the zoom. With this projector it is a 12' to 25' throw for 120" diagonal, so I would be at about 14-15 feet from lens to screen if possible.
I can easily mount it at this distance.
The height of the projector should be just a few inches above the top of the screen if possible to minimize the amount of lens shift used which will help eliminate any possibilities of lens aberations.
Do you mean the center of the lens should be at the same level as the top of the viewing part of the screen? Thought I saw that somewhere, but not sure.
The screen, I am guessing is a tab-tensioned version as you hopefully did not completely waste your money on a non-tab-tensioned motorized screen.
Yes, it is a tab-tensioned screen, I do not want to deal with a wavy screen down the road.
The room, if it is not painted dark, really should be for best results. This includes walls and ceiling.
My walls are all set, although I used a Satin, I will probably go over them again with the same deep maroon in a flat to reduce light reflections. My ceiling on the other hand needs to be repainted I see now.
Likewise the carpet should be as dark as possible.