Across:
1 Puts a new shine on (TIDIES) news from West Indies ('news' from 'West Indies' = tidies = TIDIES),
4 Stroke by a night-watchman (cricketeer), for one (OFF-DRIVE), going amiss (OFF-) with ambition (-DRIVE) (OFF-DRIVE),
9 Passed time (KILLED time) in Kildare (KILL-) with writer (-ED) (KILLED),
10 Poser (CLUE-) from takeaway (take away = -LESS) (CLUELESS) has no idea (CLUELESS),
12 Translate (FIGURE OUT) ‘craic’ (craic), in a manner of speaking? (= homophone indicator) (‘craic’ = ‘crack’ = FIGURE OUT),
13 Poser leaves sour grapes (‘poser’ leaves ‘sour grapes’ = urgas = SUGAR) for something sweet (SUGAR),
14 One of those stoned types synonymous with Queen (VICTORIA PLUM called after Queen Victoria) found in The Seychelles (VICTORIA is the capital of The Seychelles) with Deep Purple? (PLUM) (VICTORIA PLUM),
18 Too eager (TRIGGER-HAPPY) to square (T- square) with sailor at times (-RIGGER-) in good spirits (-HAPPY) (TRIGGER-HAPPY),
21 An indicator (ARROW) of overall (= reverse indicator) anxiety (worry) endlessly (y) (‘worry’ without ‘y’ = worr = -RROW) alarming from the start (‘Alarming’ from the start = A-) (ARROW),
22 It’s about (RE -) vet (-EXAMINE) (RE-EXAMINE) in study again (RE-EXAMINE),
24 One (I-) sports (= anagram indicator) fan (fan = -NFA-) has a type of pad (mouse pad) that’s not finished (e) (‘mouse’ without ‘e’ = -MOUS) (INFAMOUS) and well-known for its poor quality (INFAMOUS),
25 Party (DO-) slump (-SAG-) relates to extreme indiscipline (extreme ‘indisciplinE’ = -E) (DOSAGE) – this might come precisely as a shot in the arm (DOSAGE),
26 It’s still (serene = SEREN-E) about Bill (-AD-) (SERENADE) – the romantic type heard under the balcony (SERENADE),
27 Scores an equaliser (LEVELS) in line (LEVEL-) with last defenders (last ‘defenderS’ = -S) (LEVELS).
Down:
1 Remove half of them from Number 10 (TAKE FIVE from the number 10) and relax (TAKE FIVE),
2 The committee (DELEGACY) of French (of = DE-) inheritance (-LEGACY) (DELEGACY),
3 Turns up (= reversal indicator) in agreement (in ‘agREEMEnt’ = reeme = EMEER) with Arab leader (EMEER),
5 Time in Boston (FALL) for two sides (‘TwO’ sides = TO) and slices (PIECES) (FALL TO PIECES) of crumble (FALL TO PIECES),
6 Wild (= anagram indicator) pet housed (pet housed = DEEP SOUTH) in American region close to Mexico (DEEP SOUTH),
7 One (I-) finishing sentence (finishing ‘sentencE’ = -E-) in jail cell (cage = -C- AGE) (ICE AGE) in a major cold snap (ICE AGE),
8 Guard (ENSURE), engineer (E-), nurse (nurse), butcher? (= anagram indicator) (nurse = -NSURE) (ENSURE),
11 Not keeping up (LOSING GROUND) with one of the symptoms of coastal erosion (LOSING GROUND),
15 Gets into rows regularly (OARSWOMAN) for pulling a few strokes (OARSWOMAN),
16 Goes off (SPOILAGE) wise guy (sage = S-AGE) over pressure (-P-) put on Greece (Greece) state (= homophone indicator) (‘Greece’ = ‘grease’ = -OIL-) (SPOILAGE),
17 Ceremonial fire (PYRE-) seen (seen) changing direction (= reversal indicator) (seen = -NEES) (PYRENEES) from a height in France (PYRENEES),
19 Graduate (MA-) can (-TIN-) open schedule (open letter of ‘Schedule’ = -S) (MATINS) with early morning service (MATINS),
20 Would rather vote for (PREFER) Macron from France? Mr Rope! (‘Macron’ from ‘France Mr Rope’ = ferrpe = PREFER),
23 Sounds like (= homophone indicator) one way in (‘a door’ = ‘ADORE’) to worship (ADORE).