I struggled off and on over several days, but finally got there with the aid of the forum and my nephew, who explained the preamble to me. I had completely misinterpreted it initially. When I did understand, I did not like it. Too many of the solutions seemed to have little logical connection with the theme. in so far as there is one. eg "mashed POTATOES", leading to two unrelated words which just happen to be made up of the letters of the key word, but can only be confirmed from the crossers.
However, the reason for this post is to ask: Is there a consensus on the 'U' versus 'O' in 34A? I note different views have been expressed, without a conclusive argument either way. So I remain in two minds.