I'm a Rev War re-enactor. I have a Fowler. (A Bess, a Jager, a Virginia rifle, a canoe gun and about 5 cap n ballers.) Making paper cartridges is very easy. You don't need any glue or special secrets to load your Fowler.
I found a websight that shows you the best way to roll and fold the paper. It's from a Civil Warr re-enactor, but the cartridge is the same.
http://www.3rdalabama.org/roll_cart.htm
After you roll it, using your dowel, place the shot in first, then the cushion wad, then the powder card, then the powder and fold her up.
Tear the paper with your teeth, pour a small amount of the powder into the pan, then the rest down the muzzle, and just ram the rest home on top of the powder...You're loaded.
Of course making sure that you ram the wad end (the end you opened) in first. The paper of the cartridge itself will be your top card.
You will see that when making the cartridge, you twist that top end of the roll, it becomes as strong as a paper card.
My only cautions are that you may have to play with the load volumns again, I tweeked mine just a bit for my .62 fowler, and you may have to play with different pappers to find one that blows open when it leaves the muzzle.
Get a "Belly Box" Cartridge box for your belt, and you're ready with 12 to 20 loads.
Happy shooting.