I do think that logically, based on how other things happen, it now seems to me that the room may have been intended to be in the vane, but it still doesn't seem right to me, and the look of the vane does not help me buy it any better. That room just doesn't seem to belong perched inside that dome on the vane. In the film "The Black Hole", a lot of time is shown whilst the crew is traveling throughout the Cygnus early on, taking air cars through a travel tube, and even a long elevator up to the command tower. I totally believed the layout of the ship as it was shown to me. Now I realize they had different priorities in that film to build up tension as they traveled trough the empty ghost ship, but the fact that the door closes behind luke, and just seconds later he is in the carbon freezing chamber, just adds a level of confusion to the viewer. A quick shot of Luke traveling through the tube/hallway to get to the vane is all it would have taken for us to get it.