We have a member who is a rep. for the Combi Plan and felt that neither the filling through the bottom (I believe he suggested this shouldn't be done), nor the rubber bands should be necessary if it were assembled and used properly. I just found that these techniques work for me, make things a bit easier and have no downside to them in terms of the developed negatives.

P.S. Pic in the previous post is exactly how I fill and empty mine.