Got all the windows sealed, and started to put up walls:

I may have misread how to install the grooved side trim on the Left Diagonal Wall (just rechecked-- no, I don't believe I did misread)-- should've dry-fit it, because the Left Front Wall does not fit in place the way it ought. There is a huge gap between the 2nd floor and the Left Diagonal Wall now. I added some matboard to the 2nd floor to fill out that gap; I think that it will not affect placement of anything higher in the structure though, so it's OK. These grooved vertical trims are tough to keep square, and then on top of it all one has to make allowances for them in ceilings and floors.

Prepping the underside of the 2nd floor with some ceiling-works; trying something fancy with a doily, a wooden medallion from HL and a decorative button, in small tribute to Robin Carey's wonderful ceilings!

Figured out that I really needed another Flora Lites battery pack, so found one (20" leads) on eBay. Worth it. The battery packs that I had found recently on Amazon have the on-switch on one side of the pack and the batteries are inserted on the other side. Unless one is going to dangle the pack from the middle of the ceiling, this really doesn't work.

Got my 1st floor paper templates laid out, and framed that window box while I can still get to it.