Popper, you are the first to make any mistakes when lowering their TM. Not one of us has ever made a mistake while lowering.
For your bed, you may get a Coleman air bed. I have a king, so my size won't fit yours. But, I have a 12v air pump which inflates both mattresses in about 3 minutes, total. You could likely get one mattress that would fit. The, you just deflate, and all bedding can stay in place. Much easier than trying to store the foam topper (we have one, too).
I have closed the rear without putting the front slide in. Also have put it down without raising the steps. Have forgotten to release the bed-catch pins before putting steps up, stowing door.
Don't worry about the mistakes. That's how we get familiar with our units.
