I am still working on the attic and needed to add a few more wooden caps around the tower opening. I added trim along the edges of the gables and then installed the gingerbread.
To fit the acrylic back cover onto the dollhouse, I had to modify the roofline and gingerbread. The modifications are highlighted in the photo below. The gingerbread pieces were too long, which would have blocked the acrylic back cover. I cut 2 inches off each piece and rejoined them in the middle to maintain their design. After spackling and painting the joint, you can't tell they were shortened. I also added trim to the gable edges and positioned the gingerbread behind it to keep the acrylic cover in place. I created a ledge along the edge of the third floor for the acrylic back cover to rest on when applied. Additionally, I shortened the gable roofs in the middle where they meet, as their overhangs were too long and would interfere with the acrylic cover.
Finally, I primed the roof with a dark paint to prevent raw wood from showing through the shingles and added roof trim.
