Just browsing...

I noticed all too late that the background got clipped a little near the far left corner. Fortunately it was easily remedied in photoshop with a small hard brush. The couch in the corner on the other hand... Some pretty messed up stuff was going on with it's shading and I don't know why, so I cropped the image to exclude the worst of it. My best guess is that it is because I added it in after I baked the Irradiance Map and Light Cache and so wasn't properly included in the GI calculations. I had a similar issue once before when drastically changing the camera position wile still using a baked IR/LC file which is dependent on the camera view when rendered.

Rendering time was 51 minutes.