Yes, thanks, 
chrise, I think for some reason I had the shift key down. Unfortunately this site doesn't allow you to preview a comment before posting.
I'm still baffled by the supposed connection between 12A and 21A - particularly given the 6th letter of 21A.  Googling shows no results when I use 1-4 of 12A and 1-6 of 21A as two words. I'm sure I have the right solutions as I have most of the crossers.
Not sure what the 'theme' might be; for some reason this seem to be readily deducible by those who complete these in 20 mins or less, but not me. There are a few food items in the solution but that's not helping me with 5 ones I can't do that I'm giving up on. 
17A is particularly resistant to my limit brain power!