Solution to 5D 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
9 Understand proper, that is to gain some scholarship (7) REALISE {REAL}{I{Sc...p}E}
10 Encounter with criminal's a stretch (7) CONTEST {CON}{TEST}
11 Entertainment company at NCR takes over English Trust ultimately (7) CONCERT {CO}{NC{E}R}{t..sT}
12 To live, heart should beat inside, so respire (7) BREATHE {B{HEART*}E}
13 Almost certain to give, that is give up (9) SURRENDER {SURe}{RENDER}
15 Sleets at present aboard ship (5) SNOWS {S{NOW}S}
16 Skeptics can't be quiet. Complicated, most fed up (7) SICKEST SKEpTICS*
19 Assembled with society, plan to meet journalist (7) STACKED {S}{TACK}{ED}
20 Wife finally leaves for a skillful tailor (5) ADAPT AD(-e+a)APT
21 Casualties as car in front at distance crashes (9) ACCIDENTS {Car+DISTANCE}*
25 Incentives to get a vehicle? Nonsense scheme primarily (7) CARROTS {CAR}{ROT}{Sc...e}
26 Smoking some pot's acceptable very strongly in Germany (7) PUFFING {Pot}{U}{FF}{IN}{G}
28 Test is in old compound (7) EXAMINE {EX}{AMINE}
29 Enters hurriedly and takes a downpayment (7) EARNEST {ENTERS}* over {A}
DOWN
1 Rates of crispies is reduced in confusion (6) PRICES CRisPIES*
2 Means chap's nerd almost (6) MANNER {MAN}{NERd}
3 Number 4 is seen in fine clothing (4) FIVE {Fi{IV}nE}
4 Analysed a cricket match with editor (6) TESTED {TEST}{ED}
5 Cold people having beer? Good, chill first and serve (8) ?C?B?R?S (Addendum - ICEBERGS {BEER+G+C+I+S}* - See comments)
6 Down? Rise and believe (10) UNDERSTAND {UNDER}{STAND}
7 Publication selected and hired old team leader (bachelor) (8) TEXTBOOK {T{EX}{Team}{B}OOK}
8 Worried about desserts (8) STRESSED*
14 Choose metal, cycling to club for another type of music (10) ELECTRONIC {ELECT}{(-i)RON(+i)I}{C}
16 Looked for vault to store grain? No, the other way round (8) SEARCHED {SE{ARCH}ED}
17 Say, convenor's from Switzerland, a pilot (8) CHAIRMAN {CH}{AIRMAN}
18 Shift sent far for distribution by road (8) TRANSFER {SENT+FAR}*{R}
22 Reproduced a dish topped with fish (6) COPIED {CO{PIE}D}
23 Captured leaders of Norway and Italy and showed the way (6) NAILED {No...y}{And}{It..y}{LED}
24 Observes contests where fellow is knocked out by Stokes (6) SIGHTS (-f+s)SIGHTS
27 Backing Tamil leader at stronghold (4) FORT {FOR}{Ta..l}
Reference List
English = E, Ship = SS, Quiet = P, Society = S, Journalist = ED, Acceptable = U, Strong = F, Germany = G, Editor = ED, Bachelor = B, Club = C, Switzerland = CH, Road = R, Fellow = F