Interesting point, CD. I used "performing" from the US musician clue. The "at" alone is enough to give the middle two letters of the answer and therefore "performing" is extra.
I did, like Brendan, consider the "on" in the buns clue but rejected it because (a) it's given directly, rather than a synonym and (b) the five letters that sound the age in that clue form an adjective, whereas buns is a noun. I took the "on" to mean about or concerning, thus justifying the adjectival form.