All the rooms got crown molding or ogees. This enabled me to hide the gap between the ceiling paper and the wallpaper. I painted all the molding strips I needed with the same paint as the ceilings, except for the Library moldings which were finished to look like mahogany. 2 coats was sufficient.
I attached the molding with the Crafter's Pick Ultimate glue and drops of gel super glue every 4 or 5 inches. I applied glue to the top part of the molding (glued to ceiling) and the back of molding (glued to wall). I pressed each piece in place for about 30 seconds. Again, the super glue held them in place while the Ultimate glue dried.
In the Dining Room, because the paper was not quite high enough, I purchased Rococo Frieze molding made by The Lawbre Company. Before the crown molding went up I added a strip of wood 1/8 in thick and 1" high all around the top of the room to act as a spacer for the frieze.
I painted the frieze with 2 coats of my ceiling paint, regular latex paint from the hardware store, and then I painted all the detail with Ceramcoat Metallic Gold paint and the finest brush I could get at the art supply store. I used a different bruch on each piece as the bristles got used. This step took about 4 hours per 18 inch molding strip, but it was worth it!
The other room that got a special molding finish is the Music Room. I purchased plaster moldings from Sue Cook in England. I finished it the same way as the Dining Room frieze, 2 coats of ceiling paint and detailing in Gold paint. I turned the section of the house upside down and glued them on with gap filling adhesive applied with a caulking gun. After touch ups I was very happy!