Looks like I need to start watching this thread.. I'm going to order the same material from SeymourAV, but a slightly smaller (but 16x9) screen. Did you decide to use a tilt in the material? I'm very interested in the construction details and pictures of mounting the material to your frame. I think mine will end up being VERY similar.
I can't tell from your renderings (what did you use to create them??), what is the rest of the room shaped like? Dimensions? What are your plans for acoustic treatments?