Well, I finished (agreed, 21a is wicked!) but:
12d was a guess then google then reverse-engineer the parsing;
9a ditto without the google (at first I thought it was breaking the rules, but no);
2d I don't understand the first letter, unless it's an abbrev I'm not aware of;
1a I didn't know the house in the South of France until I googled on the off-chance, so that's a TILT.
Wow. Now it's over I can start to tell myself I enjoyed it.