Solution to 3D has been deliberately left unsolved and is to be answered only by a non-regular / novice commenter, with proper annotation. Those who have answered earlier in the week, please give others a chance.
Open for anyone to answer, if not solved by 1 PM.
ACROSS
8 A purer gent styled in an engrossing novel (4-6) PAGE-TURNER*
10 Harry renounced truth about English criminal (5-3-7) UNDER-THE-COUNTER {RENOUNCED+TRUTH}* over {E}
11 Small side around river or brook (6) STREAM {S}{T{R}EAM}
12 Looks after terms of service for drunkards (8) TOSSPOTS {SPOTS}<=>{TOS}
14 Basic unit in Excel layout! (4) CELL [T]
15 Bleak day's back (5) DREAR {D}{REAR}
16 Time to run with English knight for expedition (4) TREK {T}{R}{E}{K}
17 Drive of the majority wanting small personal sacrifices! Public relations! (8) MOTIVATE {MOsT}{prIVATE}
18 Chinese silk cloth from some sponge extract (6) PONGEE [T]
19 Bury to pass stage one at England, amongst universities (15) INTERCOLLEGIATE {INTER}{COL}{LEG}{1}{AT}{E}
21 Untidiness of officer's eating place (4) MESS [DD]
22 Work during days, more confident about following one who sails on board (10) WINDSURFER {W}{IN}{D}{SUR{F}ER}
DOWN
1 Done with parent shifts! Taking time to have fun in open! (5,3,4,3) PAINT THE TOWN RED {DONE+WITH+PARENT}* over {T}
2 Seen as a relieved kind of affliction (8,7) VENEREAL DISEASE*
3 Head's cut time to call, left out AV, for example (10) ?U?T?M?D?A (Addendum - MULTIMEDIA {MULl}{TIME}{DIAl} - See comments)
4 Bug checker with nil pretences! Let about! (6,9) INSECT REPELLENT*
5 So involved in greater good (4) ERGO [T]
6 Ambassador of India, powerful in general (15) PLENIPOTENTIARY {I}{POTENT}{I} in {PLENARY} Second I from?
7 Heard 'Nehru' tweet translated poorly (5,3,7) UNDER THE WEATHER*
13 Demi Moore's movie lines, model for cold naturalness (10) STRIPTEASE {STRIP}{T}{EASE} (Correction - {S(-c+t)TRIPT}{EASE} - See comments)
20 Intimidate with large hood (4) COWL {COW}{L}
Reference List
By = X, English = E, Small = S, River = R, Day = D, Time = T, Run = R, Knight = K, Public relations = PR, Pass = COL, England = E, Work = W, Following = F, India = I, Model = T, Cold = C, Large = L
