Ok, so I saw on you tube someone using the basting spray on a wall, so I proceeded to do that on the floor of my screen porch at the cottage. It was a very hot day, and the result was ok, but let me tell you how I did it, so you don't!
I laid the backing wrong side up, sprayed it, then laid the batting on top of that and knelt on it so I could flatten it out and make it smooth....then I sprayed the top of the batting and put down the quilt top and that worked fine. As you see from my picture,...what I should have done was lay out the batting, spray it, then put the backing on top and flip it over in order to put the top on. I was covered, like tar and feather, and it didnt come off easy. The backing was pretty smooth considering I was kneeling over it. And the top was perfect.