I finally shingled the dollhouse. I recommend using templates because of all the angles.
I left the shingles their natural color. I didn’t want to stain them darker because I thought that would make the dollhouse look too dark considering that there was a lot of dark blue on the trims. When in doubt about shingle color, leaving them natural is the best solution. I applied a coat of acrylic varnish to them to enhance the color and grain.
I filled in tiny gaps around the shingled joints with wood filler. Minwax Stainable Wood Filler is the exact same color as birch veneer shingles so, covering up little gaps invisibly was not a problem.
I also shingled the bay roof. I used templates as in the large roof. I applied the clear varnish over them to match the other shingles as well.
You can visit this dollhouse gallery here.