Note, in my version 4 I had the room facing the opposite way.
When in version 4 I was having trouble with ceiling height because there is a duct across the back of the top riser area that would require a 2ft wide, by 16" tall soffit.
It also forced the top riser to be about 100" wide.
So, We just moved to a new to us home in July, and theres an unfinished room in the basement thats 26x11 that will be my theatre room.
Attached is a cad layout of the entire basement (2 other rooms are finished).
I've been learning a lot on sound isolating, screens,stages, wiring, risers...