Cheers, mate. I pretty much pinched this wholesale, if you don't mind .
Not at all. As long as your file names and variables don't contain the RR# prefix, feel free to use (and modify) the scripts and dialogue involved in that component for your own mod.
Sure, a lot of people might get violent if pickpocketed, but it's unlikely a lowly merchant with any sense would try to take on a fully armored party.
I'm afraid that's hardcoded. A failed pickpocket attempt is treated as an attack by the engine.