To say that I am struggling with this would be a massive understatement. I more-or-less have a full grid, but I cannot parse 13a, 3d, 21d, 34d and 37d. Nor can I solve 35d. Having said that I only have 24 extra words, thus far 13 in the across clues and 11 in the down clues. If these form an instruction in English I have some rather serious problems. Without giving anything away, is what I have so far looking correct?