The unclued lights (and 4 Down + N) are of a kind and along with the suggestion given by the title, they indicate how all the solutions (clued and unclued) have to be adapted before being entered into the grid. Ignore two accents and one apostrophe.
When preceded by GREAT, each unclued light yields a phrase listed in Brewer 19th edition. First prize Mrs T. Vernalls, Thame, Oxfordshire Runners-up J. Anson, London SE5; A.
Each of the unclued lights (one of two words and one of three) can be preceded by the same word which solvers must state when submitting their entry. All resulting phrases are verifiable in Brewer 19th edition. Across 1 Detached from musical backed by censor (8) 6 Thoroughfares more important than Norfolk waterways, apparently (6, hyphened) 11 Copy of period furniture with small repeat and gold backing (5) 14 Overtake again taking time out from meals (6) 16 Public showing Eastern cross by river (4) 17 Cake with bit of icing authorised at first for Athenian assembly (8) 21 They give out decorations without bits of ice (8) 25 Male or female dress. Not half! (3) 26 Efflorescence seen during Mysore hurricane (3) 28 Franchisees at liberty?
One 4-letter word is to be placed in the middle of another to yield an 8-letter solution: 6 ÷ 19 = 44: 14 ÷ 8 = 1A; 31D ÷ 37 = 31A; 22 ÷ 25D = 9 First prize John Bartlett, Shirley, Solihull Runners-up Anthony Harker, Oxford; Mrs D.
The unclued four-letter words can be paired in a particular way to form the remaining unclued lights (one of two words). Across 5 Be in contact with a jock’s love-in (6) 10 Isolation of actors Chaney and Wallach by headland (10) 12 Scar on saint is something of a problem (6) 13 Still the champion, having downed the sticky bun first (8) 16 Little US heads (5) 17 Hermes’ footwear for 100 sene at ‘The Valley’ (7) 18 Does the gallery own something like Trident?
The unclued lights are all geographical locations – paired as anagrams: 13/9, 23/28. 30/17, 34/6 and 42/33. (33 Down is a river rather than a place-name, but DONETSK (33+K) would have maintained the theme more specifically, but then it is not an anagram of OSTEND!) First prize Magdalena Deptula, Eton, Berkshire Runners-up D.G.
The unclued lights are broadly of a kind (33 differs from the others, though 33K would have been more appropriate, if it fitted in!). Each one Across can somehow be paired with a Down one. Elsewhere, ignore one accent.
The unclued lights are examples of super slang listed on pp 7/8 in the Word Lover’s Miscellany section of Chambers 2011. First prize Paul Boswell, Hook, Hampshire Runners-up M. Puttick, Montpézat, France; M.F.
The unclued lights (all but two of two words) are of a kind, listed in Chambers 2011. Elsewhere, ignore one accent.
The unclued Across lights are words abbreviated by C (= 100) and the unclued Down lights are abbreviated by c (= centimes). First prize Mrs P. Bealby, Stockton-on-Tees Runners-up Jacqui Sohn, Great Yarmouth, J.
The unclued lights, across and down respectively, are of a kind, all verifiable in Chambers. Across 4 Single instruction on small firm's photo visible to the naked eye (11) 11 Accidental but obvious choice (7) 12 Hard-hitting county fellow (6) 13 Following out, disturbed – get angry about it (9) 14 Drain away from church next to grass (5) 16 Speech from Republican lacking colour outwardly (5) 19 Impolite relative cut out 1/6 (7) 23 Crime writer's good classification (7) 24 Crazy about knock out (4) 25 Cover could be coat. Yes!
The unclued lights are CONDUCTORS (SARGENT is an anagram of the title STRANGE).
The unclued lights are of a kind.
The unclued lights, when paired 12/20, 16/33, 25/29, 31/6, 42/2, are RICOCHET or reduplicated words. First prize Mrs Rhiannon Hales, Ilfracombe, Devon Runners-up Roger Sherman, Richmond, Surrey; D.V.
The unclued Across lights, when correctly paired with the unclued Down ones, are of a kind, verifiable in Brewer. Across 4 Deer and setters disturbed fire-arm supports (11, hyphened) 11 Bits of lava surround unfortunate one (7) 13 Valentino edited modern work (9, hyphened) 14 Wader's support (5) 19 African Moslems' bad sinuses (7) 21 Isle's black pick-up (4) 23 Young tree — one that's alright round heather (7) 24 It's almost flat panic, initially! (4) 30 Medley from a couple of little girls (7) 32 In full – on the run?
The unclued lights (1A, 1D/36, 4/31D, 5/27, 15/16A, 16D, 25A/40, 42 are each the PSEUDONYM (anagram of ‘Dumpynose’) of a famous celebrity. See Brewer 17th edition revised, page 1112 et seq. First prize Mike Underwood, Auvillar, France Runners-up Anthony H.
The unclued lights, individually (each of two words), or paired, are of a specific kind, verifiable in Brewer 17th Edition revised. Ignore a diacritic in the solution at 6 Down. Across 10 Make an impression as a sculptor? (10, three words) 12 Grim death of a harvester (6) 13 Wise men deck out, when allured (8) 17 Like the Arimaspi, seductive, not hard, English at heart (7, hyphened) 18 Tune that's popular – but not in the plane!
The chain of anagrams is as follows: 40, 8, 18, 25, 22, 23, 21D, 19, 1A First prize Robert Hirst, Twineham, West Sussex Runners-up Philip Berridge, Spalding, Lincolnshire; R.B.
The unclued lights can be arranged into a chain of anagrams of 3 to 11 letters in length, with the addition of one letter step by step. Across 7 Towboat capsized in channel (3) 11 Contain grease once (6) 13 Against work — was perplexed (7) 15 Bender on river (5) 16 Two flowers of sorts in colleges (5) 17 Prudently state diocese (6) 20 Hymn to alluring female without power (6) 21 Associated feature that is in the can (5, hyphened) 27 Artificial swap of Mafia member (7, hyphened) 29 Warm-up races! (5) 30 One hug could become sufficient (6) 32 Great desire of ogre, edified (5) 34 Herbie's mallet for game (6) 36 Japanese artist's black structure (5) 37 Broadcasting with Grace — but not young Deborah (5, two words) ... 38 ...
The unclued lights are characters from The Goon Show. The paired solutions are 22/20, 32/35 and 37/9.