You don't want to know much do you?
Lets start with the floor. It is sandwiched construction. 3/8" ply > Foam > 1/8" ply. The black woven fabric you see is a breathable moisture barrier that's stapled to the bottom of the floor before it's put on the frame.
Your frame may have wings in a couple of places but the floor is set on the frame and the overhang is supported only by the floor strength. There is no extra framing for the fridge or any other loads.
The walls are stapled or screwed to the floor depending on whether the wall framing is wood or aluminum.
The roof is constructed the same way the floor is except instead of 3/8" ply they use 1/8" ply on both sides of the foam then the mambrane is layed over that.
The roof membrane is glued to the plywood decking.