1 Smooth with this rough substance (9) SANDPAPER [Straight Clue again, when will the Constructor change?]

6 Earlier religious dignitary (5) SAINT?? [Not sure how]

9 Income again from neighbourhood (7) REVENUE [RE(again) + VENUE(neighborhood??)]

10 Disc associated with Spanish dance (7) [No Idea Yet]

11 General plan of action (7) POLICY?? [Not sure]

12 Take oneself off suddenly (6) [No Idea Yet]

15 Old religious pamphlet, one about lineage (10) [No Idea Yet]

16 Large semicircular recess (4) APSE [Straight Clue??]

18 Members at grassroots level (4) [No Idea Yet]

19 Job for a learner concerned with the trade (10) VOCATIONAL [Saw it in another forum, Someone explain please, Vocation is job but AL??]

23 I hunt around for a carriage to ride in (6) CHAISE [To hunt around is CHASE. Anag of CHASE + I]

25 Orderliness in the system (6) METHOD?? [Seems to fit there]

28 I'm badly upset by such a force (7) IMPETUS [Anagram of I'M and UPSET, badly is the Anag indicator]

29 Contaminate and destroy the purity (7) POLLUTE [Straight Clue]

30 Remove all traces (5) ERASE [Straight Clue]

31 Unconscious and wildly foolish (9) SENSELESS [Double Definition]

Down

1 Doubt about what is morally right (7) SCRUPLE?? [Not too sure]

2 Short story that is new and strange? (9) NOVELETTE?? [Novel is new, not sure though]

3 All-healing universal remedy (7) PANACEA [Straight Clue]

4 Mixed type right for bridge support (4) PIER?? [Not too sure how though]

5 What exceptionally uncommon birds are (4) RARE?? [Gut Feel]

6 A fish that showed sullen displeasure (6) SALMON?? [Not Sure]

7 Our beloved country (5) INDIA [Best Clue Today ;)]

8 Fall back into illness (7) [No Idea Yet]

13 Lean over the good man to degrade oneself (5) STOOP?? [ST is for good man, not too sure about the rest of the clue]

14 Confined to a particular spot (5) LOCAL?? [Wild Guess]

17 Accommodation for top people? (9) PENTHOUSE [Nice clue, straight, yet cryptic]

18 Broken lattice relating to touch (7) TACTILE [Anagram of Lattice]

20 Detached portion of a glacier (3,4) ICE FLOE [Saw it at another forum]

21 Climbing frames left by totters (7) LADDERS?? [Seems to fit here]

22 Set again to get the blood-sucking fly (6) TSETSE [set again is the clue]

24 First Greek letter (5) ALPHA [What a cryptic and tough clue, had to break my head for an hour for this ;)]

26 She is a goddess again (4) ISIS [Too similar to the TSETSE clue]

27 Full extent from end to end (4) SPAN?? [Looks like it]