This is what the cold air side looked like. Unfortunately there was just no easy way to reroute this stuff unless I went up through the attic.

The rafter to the left of the little crawlspace hole is Thea's room's only return, and the only return from the back office. If I ever get a geothermal system or energy becomes otherwise relatively free, I need a LOT of air moving back into that greenhouse-like office/library too keep it heated OR cooled. Right now we don't even try! We just only use it 6-7 months out of the year.

The next two rafters are the return from the living room under the front windows. Very important, and the only way to cool off the outside-corner living room as well as the adjacent hallways and kitchen is to keep air moving through this return. In the winter it's fine the way it was.