Well that was a disappointment. I did quite well with the numbered clues, except, of course, for the two theme-related ones, and without an idea of the theme, I was unable to do any of the Undefined clues.
Came back to it the next day, but still couldn't get anywhere, so I cheated the two numbered theme-revealing clues ... and still cant figure out the theme, or see any of the Undefined clues.
So that's me out. Absolutely the worst I've ever done on a prize crossword. I'm off to the Everyman. Or maybe the Daily Mail quick.