Each pellet should be equal to a given number CF blocks, the filler only being refillable at empty, and the sprayer depleting as many blocks as needed for the scaffolding (or until it runs out) per spray.
It would also be very nice is scaffolding would only be ejected towards the sprayer's source, and not up or out the other way.
Why? It was a complete PITA to setup the scaffolding and fill it in properly with the CF sprayer (it always seemed to want to leave one or two blocks unfilled); I /mostly/ worked around it by starting near the old foam first; but it was a huge pain for floors and the anti-spider edge where it would often fail to fully fill to an edge or worse fill in the supports other blocks in the shape depended upon.