There are three main objects in the Photon Shooter sub-module.
Weapon Registry: A configuration object which contains all Ammo and Weapons that are required for your game to run.
Character and Player Shooter Network: A component required to syncronize all shooter actions.
Setting up the Photon Shooter sub module is a fairly straight forward process after you learn how to use the Photon module and Shooter module.
The first thing you need is to setup a Weapon Registry component and add all the ammo and weapons as needed.
Once this is done the final step is to turn on the "Sync Shooter" option in your Player Character Shooter or Character Shooter components.