All filled in apart from 31, which defies solution. I can see how possible wordplay produces a word, but it isn't in BRB. Ignoring that blank cell for the moment I have unwrapped the abaa... instruction to produce a 6 (or 7 if its pluralised) word + gibberish. Plod on ... Others appear close to giving up the will to live - should I venture on?
I've filled in the bottom half, but I don't understand the word play of 15d, 20d and 25d.
I spent a while wondering why the answer to one clue fitted the definition in another, and then read the rubric!
15d take the usual 3 letter word for 'encountered' from the top of a word for xylophones and the like.
20d alter a word in the clue to give a reversal indicator for the shortened 'short piece'.
(there isn't a 25d)
Difficult to give a hint for that one, dylan - there's an obscure 5 letter word meaning 'hired' in India that reverses, with an 'e' on the end, to give an obscure word meaning 'summon up.'