The heat is fixed -- HVAC guy did in fact show up, although not as promptly as we might have hoped. He installed some pipes and voila! Leak-free heat. So that's good.
As for the progress that's been made downstairs, I haven't got any pictures, as my camera battery is dead and I haven't decided what to unplug to plug the charger in. Life will be so much easier when our whole house has functioning electricity and fully-installed outlets. Anyway, what's happened is that Don has actually managed to completely line the downstairs walls with tarp. This is going to serve as makeshift insulation, creating an air barrier between us and the outside. It's not much, but it's better than nothing. He's also lined the ceilings, both to prevent hot air from rising to the soon-to-be-unused second story and to prevent plaster dust and construction debris from falling through the floor and severely damaging something, like the cat. It's all about the preparation (he was an Eagle Scout! Did you know? As far as I can tell the only thing he gained from it was a lot of experience playing Magic: The Gathering and the ability to tie seemingly complicated knots that don't actually hold things together [I'm pretty sure bungee cords were invented to save us from Eagle Scouts]).
So, there is in fact a possibility that by the time he flies out for his business trip on Sunday (still no idea how I'm going to entertain myself for a WHOLE WEEK without somebody to bicker with), we could in fact have at least the bed downstairs. And maybe the desks. This is complicated by the fact that I'm going to the Bead Society of Greater Washington's Bead Bazaar with Lindley tomorrow, and we still have to do a lot of laundry, but still! Heat! Not having to huddle in bed under the down blanket at 7 PM because it's the only place to be moderately warm! Very exciting.