All done apart from the usual incomprehensibility of some clues:
34ac Worn strip-light fixture, so you're told? Must be SASH, but why?
44ac Infection common, maybe it's caught through the rectum. Must be LEPRA, which takes care of 'infection', but then ...?
19dn Rousing delivery from best friend's brother. Solves itself as FRA, but what do first five words of clue mean?