Can you use less than the whole mold?

You can do as you suggest. Each section of the mold is separate from the others so you can use only a part of the mold or all of it and move pieces after they have solidified. I've done both and both work easily well.

You can use which ever spaces you want and as many as you want. The walkway I made was about 2 and a half molds wide. I filled 2 molds in the middle and then sort of made rocks to go down the sides. It is difficult to fit the mold around the two middle sets so I made the fill-in rocks in another place in the yard and then when they dried I put them in place.

If you want to fill only half of the mold due to size constraint of the area for the path, you may certainly do so. Since the WalkMaker® should be placed in its intended final location before the mold cavities are filled, there should be no concern with the finished product weight – it should not need to be moved. If you opt to fill in only some of the cavities, keep in mind that this would present potential for a tripping hazard due to large gaps in between the “stones”. Please call the QUIKRETE® Technical Center at 1-800-282-5828 if you would like to discuss further.