The original puzzle may be found here.
Lots of great clues here with a good variety which covered nearly all bases. 14A was excellent, as were 25A and 22D. 1A and 27A were impressive anagrams.

| ACROSS | ||
| 1 | WALPURGIS NIGHT |
Right wing pals assembled outside university, April 30th (9,5)
|
| (Right wing pals)* around u{niversity} | ||
| 10 | AUDIT |
Check gold and diamonds investment after being cleaned out (5)
|
| Au(=gold symbol) + d{iamonds}(=abbrev used in playing cards) + i[nvestment]t | ||
| 11 | NASHVILLE |
City finish off Aston Villa – he’s getting sacked (9)
|
| ([Asto]n Villa he’s)* | ||
| 12 | PROXIMO |
President features in video plug next month (7)
|
| Xi(=Xi Jinping, current Chinese president) in promo(=video plug) | ||
| 13 | NARWHAL |
Ran around with young Prince Harry, the horny beast! (7)
|
| Ran< + w{ith} + Hal(=nickname often used for Harry) | ||
| 14 | THE UNTOUCHABLES |
Costner led its cast – lowest cast, by the sound of it (3,12)
|
| Hom of lowest caste, referring to the dalit or untouchable caste in Indian society. | ||
| 18 | CHARLES GOODYEAR |
US chemist‘s rosier update on “Elizabeth: annus horribilis”? (7,8)
|
| CD i.e. Charles having a good year as opposed to Elizabeth having a bad one. | ||
| 20 | ELUSIVE |
Difficult to catch scoop paid out ten cents (7)
|
| E[xc]lusive (removing X(=ten) c{ents}) | ||
| 23 | DOCKERS |
500 uncultured Aussie blokes who emptied a few schooners? (7)
|
| D(=500 in Roman numerals) + ockers(=slang term for uncultured Australian males) | ||
| 25 | SACRISTAN |
The Devil claims Sir Charlie, retired church worker (9)
|
| Satan(=the Devil) around (sir C{harlie})<. Charlie is C in the phonetic alphabet. | ||
| 26 | ALL IN |
Dropping to the floor naked, absolutely knackered (3,2)
|
| [F]allin[g] | ||
| 27 | ANTIDEPRESSANT |
Doctor patented an SSRI drug (14)
|
| (Patented an SSRI)* | ||
| DOWN | ||
| 2 | ANDROMEDA |
Star group‘s uncovered landau touring airfield (9)
|
| [L]anda[u] around {aero}drome. The def here refers to the star constellation. | ||
| 3 | PUTTI |
Chubby lads in Lilliput, titchy (5)
|
| Hidden in Lilliput titchy. The def is the plural of putto, a word for a winging cherub often depicted as chubby. | ||
| 4 | RANCOROUS |
Managed my no-frills accommodation, full of bitterness (9)
|
| Ran(=managed) + cor(=my!) + [h]ous[e] | ||
| 5 | IBSEN |
Norwegian playmaker starts for Ipswich, bags three points (5)
|
| I[pswich] b[ags] + SEN(=three compass points). Ibsen was of course a playwright rather than a footballer. | ||
| 6 | NEVERLAND |
Final appearance of Ian Lavender working US ranch (9)
|
| ([Ia]n Lavender)*. The def refers to the ranch formerly owned by Michael Jackson. | ||
| 7 | GALAH |
Brave knight left adult daughter a pretty cockatoo (5)
|
| Galah[ad](=Sir Galahad losing a{dult} d{aughter}) | ||
| 8 | TRELLIS |
Climbing frame exhausted Trevor Peters (the novelist) (7)
|
| T[revo]r(=exhausted referring to losing contents) + Ellis (Peters), the pseudonym of the novelist responsible for the Cadfael mysteries. | ||
| 9 | CARPET |
Reprimand moggy, having crapped inside on a regular basis (6)
|
| Cat(=moggy) with even letters of crapped inside | ||
| 15 | NULLIFIED |
Rendered invalid, I’d suffered with Nile flu (9)
|
| (I’d Nile flu)* | ||
| 16 | CLOG DANCE |
Measure fit for wooden shoes? (4,5)
|
| CD – a measure is a type of dance. | ||
| 17 | LLEWELLYN |
Nelly getting excited when cuddling fit Welsh lad (9)
|
| Nelly* around well(=fit) | ||
| 18 | CHELSEA |
Part of Tuchel’s earlier team (7)
|
| Hidden in Tuchel’s earlier | ||
| 19 | RESENT |
Begrudge papa leaving here (6)
|
| [P]resent (papa is used as the P in the phonetic alphabet) | ||
| 21 | UNCUT |
Like a rough diamond when sober? (5)
|
| CD/DD. Cut can mean drunk, so uncut by extension would be sober. | ||
| 22 | ESTOP |
European turning over a fortune in bar that’s legally approved (5)
|
| E{uropean) + pots<(=a fortune). Estop is a legal term for preventing something. | ||
| 24 | CRASS |
Boorish Conservative, right idiot (5)
|
| C{onservative} r{ight} + ass(=idiot) | ||
Very much appreciated the appropriate surface of 27ac (ANTIDEPRESSANT) and the &lit-ish feel of 18dn (CHELSEA) given that Thomas Tuchel did manage that side in 2021-2.
Excellent stuff. I’d only come across WALPURGIS NIGHT in the German before. CHELSEA is nicely &littish.
Ta Knut and Neil, nice set of clues. Charles’s bonus annus was great fun. Couple of shrugs; might’ve sussed Pres Xi if I’d revised; and, ditto Petert @2, Walpurgisnacht is familiar from something chez the young ginf, but absy no idea what (lit, or liede?). Hey ho, always happy to learn.
Knutting wrong with this puzzle, and a helluva lot which is very, very well thought out.
The setter has taken us through the gamut of grief, from EZ to VH. Perfectly clued, with so many lines of thought, and a great variety.
Like Petert@2, I was on the WALPURGIS NACHT express, instinctively, but no quibble.
Hands up, feet down, I don’t get CLOG DANCE, in 16(d), but I bunged it in.
Another great crossword from one of the Indy setters, I suppose we must gather the rosebuds, whilst we may.
Great stuff, Knut & Kneal H, thank you, both
A tricky but overall enjoyable start to the week
Several answers I’d NHO, but WALPURGIS NIGHT and ESTOP were the only 2 that stumped me. The others I worked out from the wordplay (as is often the case)
PROXIMO also got the better of me as I was thinking of US presidents only and didn’t consider the rest of the world – I also thought that OCT might’ve been in the answer as ‘next month’ is Oct (at the time that this puzzle was published)
Favourite clue was CHARLES GOODYEAR, although with the recent news re: Earl Spencer he might not be having such a good year as he hoped!
Cheers Knut and Neal