Molding joined at the corners

[zoome]

make it one as it goes around the corner. That should work.

You can select the room a and make a room molding polyline with a click or two. It would match the inside perimeter of the room.

You can also select the room and go to the moldings tabs to do something similar. I think you might be taking the long road to where you are going.

(stop thinking like a trim carpenter - you did it the way that they would do it ... Did you cope or miter the inside corners? Just kidding ...)

Zoome