I was dreading the thought of having to very carefully cut out each window, there are about 40 of them. I went about this problem by 3D printing each window frame. I then laid them out on a sheet of styrene and held them in place using small balls of clay.
Once the window frames were laid out, a dam was built around them using styrene strips. Then Smooth-cast 300 was poured into the areas surrounding the windows. Once set, the panel was sanded and trimmed.
And this is as far as I've gotten. Spring has arrived and I've been kept busy in the garden and not in the mood to do too much modeling. So hopefully I'll pick this project up again in the winter, or next. I've got too many projects it gets hard to commit to just one.