The lattice is working out better than I expected. The pieces I have are long enough to lay on the lawn, go over the edge and extend to the end of the ledge. I just place them at the right spacing of the hulls and the boat slips right into the water. Pulling it out is a snap. I will say that if I don't pull it up over the edge of the grass in one shot, it will slip right back in the water.
I have 2 different pieces of lattice, one with a 2" hole and one with a 1" hole. If I had to buy one I'd probably go with the 1" hole. I used them about 6 times now and they seem to be holding up real good. I do use them on a fairly smooth, mowed lawn.
Have no idea if they float, but if I had to guess I'd say no.