Genius 240 - Guardian

[Matakari]

Good evening, my answers for this batch proved
to be quite wrong! Your hints should help me
to correct them and steer me in the right direction
this time. Thanks in advance!

ACROSS:
●5 Group still welcoming conservationists ( 7 )
●6 Social change in America for museum workers ( 7 ) FRAMERS ?
● 8 Judge gathers decree ultimately must be reversed ( 6 )
●9 It's played in Africa either side of Kenya ( 4 )
●13 Yellow colour seen in atmosphere? It might be this ( 6 )
●15 Most vulgar fan of Labour PM uncovered stealing French art ( 8 )

DOWN:
●1 Leader of government bothers to get hired vehicles ( 8 ) HARRIERS?
● 11 Idle, posh and artless court bores ( 8 ) CALIBRES ?
●13 Persian queen sans husband hosted by reportedly wise listener in the past (10 )

[Neveracrossword]

Your three suggestions are wrong. I havr tried to think of hints, but the many given earlier didn't seem very effective!

[ProfessorMaisie]

5 'still' in the sense of silent, so think of another word for that (5 letters) around NT (National Trust) that will give you a group of musicians.
6 A 'social' is a party (the usual 2 letters) 'change in America' = American coins (5 letters) then check out the resulting word in Chambers, it's quite obscure.
8 '(to) Judge' is the def (to value?) a 5 letter word for 'gathers'/'gets together with' + E [all reversed].
9. When you see 'either' in a clue it usually means you've got OR in the middle of the answer, so 'either side of Kenya' is ?OR? (it's an African musical instrument).
13 'yellow is usually the tincture OR - 'atmosphere' is something like a halo - answer is a weather phenomenon.
15 It's a supporter of the Labour PM (Tony...) [8 letters, but minus the 1st and last letters] around ES (French) - and whenever there's 'most' in a clue it'll end ...iESt, then check out Chambers for the dialect word.

[ProfessorMaisie]

1 you've almost got the right word, just lose the 'r' and put it after G ('leader of G[overnment]') then check Chambers.
11 'Idle' is the def, 'posh' usually means U, so it's going to start UN... and 'court' will give you CT + (so the 5 letter word for 'artless'/innocent starts with N...).
13 reportedly 'wise' means it sounds like 'wise', so it's Y+Y around EST[h]ER... def 'in the past'?

[Neveracrossword]

Well done, PM - my attempt resulted in very long screeds, trying to be generous, and I gave up!

Matakari, I hope you head off in the right direction now.

[ProfessorMaisie]

I think the hints you've already given (and the others) were all very well pitched, Neveracrossword (but could there still be some tweaks to come?}.

[Neveracrossword]

Thanks, PM, I was full of good intentions - I was the one who suggested Matakari tackle this puzzle, I didn't expect it to be so ...problematic, I hoped it would be fun!

[Matakari]

Thanks immensely, ProfessorMaisie, for this magisterial lesson in parsing which I thoroughly enjoyed. Only 15a is still resisting me. My grid is looking good, just a few more clues which I'm trying to fit into the jigsaw now. I'll probably give it a rest and go to the Spectator hoping that I'll be able to maintain my standard of the past few weeks.