Thanks Nick. It was definitely trickier then having someone else help, but even though it took longer, I got there in the end.
Here's some more updates on the sofitt and screen casement.
This is the projector alcove showing the edges where the rope light stops. I didn't want the rope light glow affecting the image, so stopped it short. Should also create a nice little feature.
The area reserved for the screen casement. At the back left you can see the start of the front of the ropelight sofitt section.
Testing the casement fit using the gyprock lift. This will enable me to get the exact fit with the gyprock around the lip and the top/rear support pieces. Bit of extra work, but doing this now before I gyprock and install the insulation will pay off if there is any errors.
It fits! I'm a bit concerned about the length actually. The screen maybe too big for the height I want the bottom cabinet to be. Either a different screen, a lower cabinet, or a speaker behind the screen seem to be the only answers.
Now that the casement was in there I was able to work out the back supports for it.
This is one of the holes where the ducting comes in. I've started to contain it with mdf and green glue and extra insulation inside. Hopefully it contains some of the sound escaping and getting in.
So what's up next?
Well I've been doing some research on the in and out exhaust fans for the projector alcove. Originally I was just going to place the projector in the space, and since the AE7000 vents forward, was hoping there would be enough space in there to intake and vent from the front, and maintain a decent temp. Well after testing the projector with the screen mounted, I see the heat it generates is quite substantial, and also the noise is not something I want to listen to while watching a movie. So I've been exploring venting options, and also researching hush box builds. I have a few ideas on what I want, so that's what I'll be working on next.