1 Do at this place (4,4) SAME HERE [As in DITTO]

5 Maintenance in a State fort (6) UPKEEP [CVasi : State - U.P.fort - keep ( see Dictionary)Maintenance - def ]

9 Following points go to actioning (7) ENSUING [CVasi : Following - defpoints - E Ngo to - connectoractioning - suing (going to court)]

10 So-so bit dished out by instrument players (7) OBOISTS [Anag of SO SO BIT]

11 Our sailors and detectives knock off the top of a barrier in a happening (9) INCIDENCE [IN(Indian Navy) + CID(detectives) + FENCE(Barrier) - F(top of the barrier) - CLUE OF THE DAY??

12 For example, about to observe retreating birds (5) GEESE [For example is EG and to observe is SEE. Anag of EG & SEE]

13 General is back: first to see slippery characters (4) EELS [General is LEE and back becomes EEL characters makes it plural]

14 Humiliation in a subterranean vault (9) ABASEMENT [A + BASEMENT]

17 A little something recollected in sea song (9) SEASONING?? [wild guess, anag of in sea song]

19 Spots champions (4) ACES??

23 In Kulittalai, famous come-back of a crime syndicate (5) MAFIA [Direct Clue??]

24 The newspaper without the supplements (4,5) MAIN ISSUE [Direct Clue]

25 It often upholds an address (7) LECTERN [Direct Clue?? Explain please??]

26 Four collect way-out stories on art objects (7) IVORIES?? [CVasi : Four - IV way-out stories - 'stories' from which ST (street, 'way') is removedart objects - def ]

27 Oppose wayward sister (6) RESIST [Anag of SISTER wayward is the Anag indicator]

28 Having an occupation (8) TENANTED [Direct Clue]

Down

1 Al leaves Special Staff, for example (8) SPECIMEN [AL leaves SPECI AL MEN]

2 Some ignoramus I called to a kind of film (7) MUSICAL [Hidden Clue - ignoraMUS I CALled - what is the indicator here though??]

3 Heady arrangement? (6) HAIRDO [Direct Clue]

4 Damn! Nag, bear no pieces to the junk-dealer (3-3-4-3) RAG AND BONE MAN [Anag of DAMN NAG BEAR NO]

6 This won't make you a champion in field (4,4) POOR GAME ?? [Explain please??]

7 Direction in which former bowler's bird appears (7) EASTERN [CVasi : Direction - def for reqd word easternformer bowler - EAS (ref. to EAS Prasanna, former test cricketer)bird - tern]

8 Bill, the message writer (6) POSTER [CVasi : two def Bill - poster as in 'billboard' message writer - one who writes - one who posts - poster ]

10 Easily upset, it revives one's writhing (13) OVERSENSITIVE [Anag of IT REVIVES ONES]

15 Jailbirds who have freed themselves, perhaps (8) ESCAPEES [Direct Clue]

16 Foolish people the southern journalist evaluated (8) ASSESSED [ASS is foolish, ED is editor aka journalist]

18 Brings about cinematic devices (7) EFFECTS [Double Definition]

20 I cuss at wicked logician (7) CASUIST [Anag of I CUSS AT]

21 One who beams at you may be a southern athlete (6) SMILER [S + MILER]

22 North Indian drink to a girl (6) NICOLA [North Indian (NI) + COLA(drink)]