I finished installing the last roof piece, which is a small part that goes on the final opening of the back side of the roof. I painted it white on the interior. There is no need to wallpaper it. It is hardly visible, but make sure you do paint it to match your interior trim. I applied trim to the bottom joint of this piece, on the interior. The sides have to be spackled, so that any gaps are hidden.
I used wooden "buttons" or caps for the joints where two trim pieces meet.
I applied dowels to the ceiling joints. This gives the roof more support and hides any visible gap.
I also applied a special trim along the roof eaves, a few inches from the edge. This trim is so the acrylic back cover will not fall inwards when applied to the attic. I circled it in one of the photos below. I applied it to both gables on each side.
As you can see it took a lot of custom trim to make the attic look nice, but it still needs more work.
