Well, I have taken a lot of pictures this week of various steps, and I am debating whether to include them all. Including them might help anyone who needs to understand step-by-step what I am doing, but it is going to make for a very long post. Perhaps if I make the pics a small size?
I started out with a marathon wallpapering session in the attic. I found this tricky because of all the angles and crannies, and I needed to be careful as I didn't have enough wallpaper that I could afford to ruin sheets of it. I also had to think through what should be the logical order for papering, in order to achieve a neat result. If you are not interested in wallpapering, then you can just skip the whole next section of this post.
I wanted to complete some of the finishing details while I still had full access to the attic area, before I glued on the roof sections.
I had a bit of an issue with the bathroom door, as the Grandtline doorframe was more shallow than the foamcore wall. So I covered over the exposed foamcore with very thin strips of wood, and painted them to match.