My take at using guns
Change the first paragraph of Life in Zahndorf to read:

The Villagers of Zahndorf are a simple folk. They can either be Healthy, Wounded or Dead (tracked in the GNDT), and all Villagers start the game Healthy. Whenever a villager becomes Dead for any reason, the Mayor will make a story post announcing the fact.

Add a new subrule of “Items”, called “Guns and Bullets”:-

Any living Villager who has a Gun may, as a daily action, attempt to shoot any other Villager (their “Quarry”) by privately announcing this intention to the Mayor, and specifying the ammunition they are using (lead or silver). A gunman can only use silver ammunition if they have a Silver Bullet in their possession, and must reduce the number of Silver Bullets in his Inventory by 1 when making the private announcement.

Within 48 hours of receiving such an intention, the Mayor should determine the results of the shooting as follows:-

• If the Quarry is currently the Patient of the Doctor, there is no effect on the Quarry. The Quarry shall be privately informed of the gunman’s identity, and the Mayor shall post a blog entry announcing that a gunshot has been heard.
• If the Quarry is a Werewolf and the gun was loaded with lead ammunition, there is no effect on the Quarry. The Quarry shall be privately informed of the gunman’s identity, and the Mayor shall post a blog entry announcing that a gunshot has been heard.
• If the Quarry is Healthy, and neither of the above cases have been met, then Quarry is changed to Wounded, and the Mayor shall post a blog entry announcing that a gunshot has been heard.

If the Quarry is Wounded and non of the above cases have been met, then the Quarry is changed to Dead

To the rule “Religious Occupations”, add:-

Villagers with Religious Occupations may not fire guns.

We can then put the effects of wounding in to the rule-set