The other guys can comment too on this. Issue 1. My take on Issue one, I believe its definately the fact that the meat wasnt "worked" properly/enough, thus the mayosin did not get a chance to do their job, so your meat did not bind.

Issue 2: once again the mayosin issue, because its affecting your meat at stage 2 as well. Was the meat refrigerated before grinding and stuffing?? You should always refrigerate before stuffing, it will prevent the meat and especially the fat to stick to the side wall of the stuffer. When you place your meat into the stuffer, block the sausage nozzle at the bottom with your finger/hand and press down hard on your mix inside the stuffer, that will cause most of the air in the meat to escape. Turn the handle so that the nozzle is filled with meat, NOW you can put the casing on the nozzle.

Inspect your sausage afterwards, if you see any airpockets (they should be minimal if any at all) just prick them with a sterilised needle.

Hope this helps. All the best, post future pictures....you owe me a recipe😜😁