I was about to start putting the house together when I realized that I had painted the mid-level floor, rather than the ceiling. At least this time the instructions made it very easy to identify left, right, top, bottom, front and back and suggested putting a piece of tape on the top back.
So I painted two coats on the ceiling I missed and the floor of the other story. Now at least the floors are painted white for whatever treatment I decide on -- wood, paper, rug, tile or just plain white.
I also dyed the shingles with the grey shingle dye, which looks awfully black to me. And, in spite of wearing gloves, I now have three grossly dyed fingers with fingernail beds that belong to someone of considerably lesser repute.