Regarding Charm, I have "familiarities" (see my post above) of "Gutterways" and "Courtly Manners". There's a penalty if you are using Charm (or perhaps Leadership, Perception) in a very low class social setting (Gutterways) or very high class social setting (Courtly Manners) without the appropriate familiarity. Imagine the charming Han Solo at an Imperial ball versus a cantina. He's probably more used to the norms and mores of the later.

Anyone make a Perform skill? If so how did that work out?

I've avoided adding new skills, simply for not wanting to deal with the headache that would come of "okay, who is this considered a career skill for?" Even FFG has run into a bit of this with AoR and their Knowledge (Warfare) skill, which honestly could be argued should be available to specs like the Mercenary Commander or even the Guardian career.

Most edge cases that might call for a new skill in other systems frankly fall under the existing skills, provided you're willing to not be overly strict in one's interpretation of the existing skills. It's worth a quick web search to look up the old Skill Monkey series, which touches on the topic of whether adding new skills is necessary, by way of discussion of how to handle a performance check? That episode provides rationale for using a number of different skills, based upon the type of performance and what the performer is looking to achieve, with a number of options being perfectly viable.

Much the same can be said of the existing skills. Need to make a skill check to suss out information from the wealthy elite as opposed to the working class stiffs and local gutter trash, all without causing undue offense? I'd say use Charm, perhaps tied instead to Cunning for this roll instead of Presence to reflect that rather than conjure up a new skill for a scenario that's not likely to occur with any frequency.