Across

1 Punishment for making changes? (9) SWITCHING [Not too sure]

6 Following? Dead right! (5) LATER [Late(Dead) + Right]

9 Market for silver gilt article (5) AGORA [AG is silver OR has something to do with gold? A is an Article AGORA is a marketplace]

10 Support with disagreeable smile (9) CROSSBEAM [A support and and oxymoron smile??]

11 Encouraging a number to take part in an audition (10) HEARTENING [TEN takes part in a HEARING (audition) giving HEAR TEN ING]

12 Still one might doubt mountain creature's existence (4) YETI [YET(Still) + I(One)]

14 Record an engineer with bearing of an effeminate (7) EPICENE [Not too sure, got this from another forum]

15 Slipped on a ship's wooden fender (7) SKIDDED?? [Explain please??]

17 Failure to remember distressed men in Eastern countries (7) AMNESIA [ASIA is eastern countries, distressed MEN is MNE in ASIA, A MNE SIA]

19 Place a coin, sir, to order cutting tooth tool (7) INCISOR [Anag of COIN SIR]

20 Was bone lazy and lied indiscriminately (4) IDLE [Anag of LIED]

22 Bill gets a medical qualification of college (10) ACADEMICAL [Anag of ACA and MEDICAL]

25 Pen put in an envelope (9) ENCLOSURE [Double Definition??]

26 Not written examinations (5) ORALS [Direct Clue]

27 Shouts at the young to sell in an organised way (5) YELLS [Anag of SELL + Y]

28 Able to communicate through the mind or by TV, say, to your father (9) TELEPATHY [TELE as in TV + PA (father) + THY(your)]

Down

1 Shatter violently by an accident (5) SMASH [Direct Clue]

2 Lois not affected with a separation (9) ISOLATION [Anag of LOIS NOT A, where is the other I??]

3 Plan to recycle liqueur (10) CHARTREUSE [CHART is plan RE USE is recycle]

4 Smoke and so cause much displeasure (7) INCENSE [Seems to fit, Explain please??]

5 Reasons for having land around the house (7) GROUNDS [Double Definition]

6 Long, white wood or birch (4) LASH [L+ASH]

7 The anthem expressly included a short melody (5) THEME [Hidden Clue - anTHEM Expressly]

8 Starts with stop, turns colour and it's over (9) REMAINDER?? [fits here, not sure at all]

13 No initial money, say, on deck for the simpleton (10) NINCOMPOOP [N + INCOM + POOP]

14 Cunningly save up four, see? (9) EVASIVELY [Anag of SAVE + IV + ELY??]

16 Drying cans roughly tied in a knot (9) DESSICANT [Anag of CANS + TIED + S??]

18 Reckon to get a bank deposit (7) ACCOUNT?? [Explain please??]

19 Abide in Germany at mineral spring (7) INDWELL?? [Explain please??]

21 No call made to a pub (5) LOCAL [Anag of CALL + O]

23 Vigorous scholar takes turn to filthy place (5) LUSTY?? [i dont have a clue]

24 It would be detrimental for the learner to take a round of the boat (4) FOSS [Explain please??]