Im working on something similar, only just starting. You'd probably have to do as I am going to which is modify the core for adding new skills, and removing all the other junk you dont need (save for final release, it's best to keep it to reffer to).
Im not sure how all the graphics work, thats my next task, but items have the Doll Prop, which is on the character, and then I believe they have 8 tiles (up,north,right,east,down,south,left,west) for the actual weapon on screen.
After Im able to modify the core and add a new skill Im going to try and figure out how to do the graphics, and then create a new Base from BaseRanged called BaseFirearms, in the addition to that; new abilities, one ability will take stamina and cause you to reload your weapon, and possibley a 'zoom' for sniper weapons ect.
First things first tho (follow along with this, it will help ya, just reffer to your "Scripts" in the RunUO folder), I need to modify the core to add a new skill called SMGRating (not sure how to do this yet, havent downloaded core at this moment, will update you if Im successful), and in SkillGump.cs I have to add a skill group called "Firearms Proficiencies" which I will put SMGRating in as well as any others I make later. Then, following tradition since SMGRating is a combat skill I will set it to be excluded from the SkillCheck.cs by setting it to false, this way you can gain like any other combat weapon.
And with that I create a new base called BaseSMG from say the BaseRanged.cs
Atleast I think this is how it will be done, its one thing to say it than to do it
