I would i create a 5 peice door that is lets say 34\" high and the top 12\" frame with glass and mullion and the bottom is full 5 peice door. Without having to create two doors?
As far as I know you would only be able to create a door like that by adding the necessary pieces from display boards and/or panels together in the cabinet editor. Each piece could even be taken into the parts editor and machined to fit together if you have or created the necessary tools/bits.
I'm not sure off the top of my head what you would use, but I know I've seen others emulate the glass as well.