re: Garage door storage

I like your progressive mind for the ever present conundrum of storage space, however, there is something subliminal in my psyche that just doesn't jell thereby compressing my thumb.
I immediately shared Sprinter's thoughts, and even though you feel complacent as door is bolted down, the fact that it is "movable" is freaking me out just looking at the pics. 
I'd be more comfortable sacrificing 304.8mm x door_length of floor real-estate for a movable stand butted up against the door... would cost more, but I'd sleep more comfortably, even if it's in your garage.
I'd be happy to let that thumb grow

if you decided to suspend a "hanging frame" from the ceiling using industrial hardware,

and a bigger for something like,

with removable shelves on French cleats.