Bill, The slab looks good. They will use RedHeads to anchor it to the slab, I would imagine.
What is that red dirt they used for fill? I would have wanted at least a couple feet more to each side graded past the slab. That looks like most would wash out from under the slab, causing it to break. Just my opinion. Also, what kind of walls? I don't see any kind of footing to hold the structure in place. Nor the weight of it at the edge of the slab.
Kenny, That Red Clay doesn't move around like this dirt does out here, you can pour a floating slab on that stuff and it look the same way 40 years from now.