Some of the quilters on the board are layering their quilts using Elmer's washable school glue. i haven't tried it myself because I can't clearly understand what they're doing. I have used it to match seams and to put on binding and it works perfectly for that.
So if you keep having difficulty using the spray you might check out layering with glue.
I use the 505 spray basting but I have only quilted lap quilts with it. I am about to try it on a queen, but I expect no problems.