tator -- i used 3/4 plywood for the floor. The walls are all built with 2" x 2" skinned with 3/8" plywood. But part of my design, which will be more evident when i take it apart, is that i overlapped the plywood. left an overlap at the bottom to catch the base, and an overlap on the sides to catch the front and back wall. the framing for the roof, actually sits down inside the walls. I wanted everything to go smooth when out in the woods for assembly. So with some forethought, everything on mine should line right back up and be square when assembled.
American by birth, Southern by the grace of God.