Hi! I am working on a yard and shop layout and will be including parking lots, grass areas and other types of ground cover. I tried using concrete slab in the objects menu for the parking area, because the paint tends to spray round areas, and I wanted mine square, but then when I went to put vehicles in the parking area, I found they were some 3-4" deep in concrete! Can someone tell me what the trick is? Do I need to sink the ground prior to putting in the slabs? Can I make sharp edges doing this? Or if I "paint" concrete, is there some way to get square corners out of a round spray pattern? Thanks for helping out the new guy!