that reminds me of the apartment that i lived in. The place had no ductwork at all. The air handler was connected to the space between the ceiling and the attic. then holes were cut around the apartment for the air to "leak" into the apt
But realize that this job is going to be acceptable to the City of Little Rock now. Masonite is a very hard material that requires a battery operated circular saw to cut it, and hammer and nails to attach it - an air nailer if the installer is a real PRO. Or for hand tools, a utility knife to score and snap it, and a caulk gun with liquid nails to attach it. But, it is very solid material that will hold up for a real long time, so it must be good!