Hello, Elle!
Let's hope the weather holds for your builders!
Lovely afternoon here!
Wednesday's puzzles are the hardest, Elle, by design.
7d, The "UN", United Nations headquarters are in Manhattan, NY. "hitch" is "yank".
12a, is to do with ice skating, a man's name, who originated this jump, and it is not Axel.
Anne B could help!
17a, a bad mouther could be a "disser"....
20 "Oz" is Australia, surrounded by a word meaning "leave" for an island, though I have no idea where it is!
25a, The "miss" is a "gal", around "nothing/o".
"Or" refers to metal, giving a "match winner".
2d, I had never heard of in my puff.
The answer is "mosh pit", believe it or not.
Not in my Chambers!
Thank you kindly for the "o-castling".
New to me, as a non chess player!
Hope this helps.