SOS for layout design help!

I have done two "hanging" layouts over the years.  They were suspended by pulleys and used a winch/hoist to raise out out of the way.  How high are your ceilings?  If yes, here's one rough concept that could work.  You'd need a couple of access hatches.  The challenge is O72 in a room that small.  The idea is a "T" shape, and you would access it from the two doors.  If you could take the doors off their hinges and use curtains, etc., that would open things up quiet a bit too.

Well, if I understood your drawing and druthers, here's what I came up with. I made most modules 30" deep so they can be raised and stored against the wall. They could also be lowered, but if you set the height of the layout beneath the large window at the top, the width of the modules might need to be reduced a bit so they could be lowered. The 2 larger modules could be hinged so they'd fold for storage. The curves and switches are all O-72. You didn't say how high the radiator was, but I assumed the layout could go over it. This should give you an idea of what can fit and be relatively easy to store. If you go with modules, you should probably do some research on module layouts to get ideas for construction.

@Burl and @DoubleDAZ This is some pretty great stuff gentlemen. I wish I could do a pull down! Ceilings are definitely not tall enough. These are both extremely helpful jumping off points to get me going. Thank you!