Hey guys thanks for helping me out!
It doesn't look like I have that option in the room structure dbx. Attached is a screen capture of my options on the room spec dbx.
I've tried just about every combo I can think of. The tool really wants to make shelf ceilings like this https://www.chiefarchitect.com/videos/watch/64/using-the-shelf-ceiling-room-structure-setting.html?playlist=96 or those nice short walls and holes in the roof shown above. I need walls that connect to the ceiling/roof.