6 across has an answer that needs treating once before entry, and I have to say it was not one that helped me finally get what that treatment is. Eyes is indeed the definition, but I think is more an example of particular types of the things defined (according to Chambers). That's partly what makes the crossword so tricky - some definitions seem a bit tenuous to me (the 12 across homophone being another example).
The latest Crossword Centre newsletter says: "You still have lots of time to solve the November Prize Puzzle, Nonsense by Craft. This may be proving to be a difficult solve as we only have 6 entries so far, although all correct." I have submitted, but don't know whether I did so before or after the newsletter was written, so can't be sure I got it right - I wasn't completely confident about all of it.