Where do you plan on supporting your coach? Any labeled "jack points" at either end of the trailer are intended for stabilizers only. The frame is not rigid enough to have those points support substantial weight of the trailer. Makes me wonder what will happen when clay swells as moisture conditions change.
Steel channel that the axles are bolted to can take all the weight you load there.
Not sure that cinder blocks are the best idea. See here
. This issue keeps coming up -- hope someone with informed opinions speaks up.