Hi BarryC
Many thanks for your help. I thought my P might be wrong. I've now got 10ac and I got 20ac a few minutes ago. I have an answer for 13ac but I'm not sure it is right as apart from "messy", the letters don't quite match yours.
I'm getting there now. I've got six of the letters in 4 down, but can't see where the last two come from in a word I've heard of. I have an answer for 21d, but I'm not sure it is right. I'm still looking for 24ac, 8ac and 5d
I'll be glad to finish and see if I can find 18 theme words!