I live America, but I make my own kielbasa at least every Christmas and Easter.
We too, only use pork shoulder or a pork butt. We season it with, 1/4 ground pepper and salt, mustard seed, lots of fresh garlic, marjoram and ice water.
This year we added a little prague powder. This is supposed to keep botulism down..Up to now we never had trouble. but a butcher told us to use it.