There are not many platforms, mostly in New England and, there, largely in New Hampshire and Vermont. But when you need to be able to set up on one, it is good to know how.
Setting up on a platform is not as hard as you might think. 1. Usually, there are gaps between the planks. Just tie a loop of cord around a stick that will fit between the cracks, push it through, twist it perpendicular to the crack and tie on to the cord. I don't recommend using tent stakes for this because if a stake slips out of the cord, it will be hard to retrieve. 2. Alteratively, run a tight line from adjacent trees or platform piers, flat to the planks and tie on to that. This does not work as well if there is any wind, but sometimes the boards are laid too close together do use trick #1. 3. If they are spaced just right, you can hammer a stake between them and it will hold pretty well.