Get a pair of flat nose pliers and gently squeeze your ball links around the ball. That will loosen them up. Just be careful not to squeeze too hard or you'll break the ball link. Also if you do it too much, the link will become loose and pop off, so do it very gently and very slowly untill it moves as freely as you'd like, a little bit at a time.

Cool video by the way . You look almost ready to start flying without the training gear. You'll find the heli alot easier to fly without it .