I didn't watch the whole video but one thing I might add is to cover your floor with an old sheet to catch the overspray. It is really hard to get 505 spray out of carpet. Ask me how I know that one.
I have been spray basting quits on my design wall. I cover the wall with an old sheet and put the quilt back on it. i stick a few pins in to hold it up. Then I pin the batting over it. I spray baste it. I start in the middle and spray it and do the top half, then the bottom half. I do about 3 feet at a time and smooth as I go. Then I add the top and do the same thing. It works really well. I plan to fix it up so I can do this down in my basement.