Quoted from MythMaker:Believe it or not though, this transition does cause some issues. The ball does hit the metal and bounce to the post and back out. We are going to need to put a piece of mylar or a ramp flap over this transition to make it more smooth in the future. Since the ball can travel both directions it is important this transition works both ways.
Maybe reverse the overlap of the pieces and put in a one-way gate? That might take away from the flow you were looking for, but it would certainly solve the problem. The other options would be to weld the two pieces together or have a machine shop laser cut the entire piece for you.