Ceiling progress (OLD room, now lost in a fire)

My Georgian study room is progressing towards getting the ceiling finished, I ordered some embossed paper and some 1/8″ quarter round wood strips to finish the ceiling. I have a round ceiling medallion ready to paint, and install after the paper is in, along with the chandelier which will need it’s wiring routed into the ceiling before the paper goes on.

I need to route a path diagonally to the angled wall where there is an open cavity behind it the wires can go down to the bottom and out through.

The quarter round molding will trim all around the inside top edges of the wood beams.

Once I get the ceiling done I can attach the ceiling to the box permanently and then the outside can be trimmed, stained and finished then.