Bs, he could move. Anyway Madara also disproves your theory. He was flying after using CT and moving just fine
No he cast it, then started moving after he let the boulders go into free fall.
Once the boulders were complete he doesn't need to hold it anymore.
Even then he was a Ten Tailed Jinchuriki.
And Nagato wasn't shown able to move, that is merely a opinion with no grounds.
Like I said your entire argument is opinion based.