Progress the last couple of days:
I usually brush on the stain but I tried this old ziplock bag trick, and it's much faster. After sloshing them around for a minute or two, I laid them out on newspaper.
I used bfishma1's idea of transferring the plan to the foam core by poking a pin through the paper template. I cut out the sides and ends and oversized window openings with a #11 blade and straight edge by connecting the dots.
I actually glued the sides and ends together, but before the glue dried, I pulled it apart. I decided that construction would be easier by finishing flat walls. I laid down beads of white glue and placed the Tichy windows as I progressed. The window width was just a little wider than 4 boards, but I could fit the windows without notching them by spacing the boards slightly. This is where my choice of a black foam base really helped. It just looks like the loosely fitting boards of an old barn. When the glue dries I'll trim the excess with a Zona saw.
Bob