(Still haven't changed my plagiaristic nom-de-croix - sorry...)
I'm 99% done - got all the thematic stuff sorted, including full understanding of the title - but can't find anything to fill 5a - can't get anywhere with the clue, which doesn't help; and pretty sure about the 4 checked letters - but even a wordsearch in the Chambers app with six wildcards plus the last two letters of which I'm absolutely certain yields no words at all. Is this word in Chambers? Can anyone please ease this lame dog over the stile without revealing too much?