+ Nice termination points, and a good example of a DIY effort to mould existing conditions to a desired end goal. From what I can see there, everything's plumb or perpendicular to the ground.

- In certain drier habitats the front speakers would be considered a bit too elevated. Also, in that room I would have been tempted to drop the ceiling down to the same level as the projection screen enclosure, at least back to the beam. I think it would "flow" a little better visually and you wouldn't chance artifacts from sound bouncing off the beam. You'd have to lose/move the fan, but your seating position is behind the beam anyway.(I'm a fan of the fan, but my feedback still stands.)

Website feedback? You don't mention your speakers, but I think I can hear what you're cookin'.
(Is Polk's registered tradmark in the public domain?)