I'm battling away on my last couple of clues.
10 D. NY ice rink contrived to break plug one put in box (13, 2 words) COR?I??RK?IC?
I think Cork/plug features somewhere and I think this is one of the entries with extra letters.
21 A. Do I sense incorrect understanding? (8)
n??e??is
I've tried to make an anagram out of 'do I sense' but got nowhere.