I have completed the grid.
I have 12 letters in the middle square. I have the two unclueds also.
Need some clarification on end game.
Do we first fill in new words for 6 redundant words and then change one letter in each?
Do the new words go in horizontally, vertically or both?
Then change one letter of each answer (best to start in the top left corner of the central grid) to make new words defined by the extra words - again, all horizontal
Not really, hankir - a bit messy though (just repeating answers in a different part of the grid - with the guide letters from the overlapping answers - didn't take any time at all).
As for the 'theme' - didn't like it at all!