It wont work. The "Profile" isnt what you see, when its loaded in to the Mullion.
But i dont do Up/Down or Left/Right in Revit. I do End/OppEnd, because of the Mirror Tools, and draw direction.
We end up with 4 for each system. End (Closed/adjacent to glass), Opp End (adjacent to glass/Closed), Center (glass/glass), End (Closed/Closed).