I have a complete grid, but am in some doubt about how to fill in the bottom row. If there is a clash between, say, D and L (ie letters 4 and 12) do I put in H (letter 8, halfway between D and L) or R (18, halfway between L and D)? Doing it this way, ie, making D letter 30, is the only reason for havinf the preamble state that A = 1, 27 etc. So i have two possible letters for each cell in the bottom row ... but that's where the brick wall appears. I know the missing letter, but its definition(s) don't help. What am I doing wrong? (There are a lot of brilliant clues, of which 37 is my favourite.)