Solution to 14D 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
1 Keep tab on for short (6) STUBBY {STUB}{BY}
4 Tough boss single-handedly crossing limit (2,6) AL CAPONE {AL{CAP}ONE}
10 A religious sign in places with workers, mostly (8) APIARIES {A}{PI}{ARIES}
12 Loud noise over piece of rubbish (8) CLAPTRAP {CLAP}{PART<=}
15 Champion gets support — is dead against moving outside (12) PROPAGANDIST {PROP}{D+AGAINST}* What's the role of 'outside'?
18 Dog sauntered out of the plant (6,6) ADDERS TONGUE*
22 Americas rejuvenated earth (3,5) NEW WORLD {NEW}{WORLD}
24 Realign correctly below a subject (8) ALGERIAN {REALIGN}*<=>{A}
25 Pitch for a work shoe (6) BROGUE [DD]
26 Capital providing cover — 11 expressed in words is sad (8) LONESOME {L{ONES}OME}
27 Love for teacher is considered divine (6) OSIRIS {O}{SIR}{IS}
DOWN
1 Forgiving the police years later for providing a digital document file (4,4) SOFT COPY {SOFT}{COP}{Y}
2 Nurse on a round — it's madness (8) UNREASON*
3 Harry stands by at first, but not regularly (2,4,3,6) BY FITS AND STARTS*
5 No small inclination, run using long strides (4) LOPE sLOPE
6 Analyse Star Wars — fools do become speechless (2,1,4,3,5) AT A LOSS FOR WORDS*
7 Align with China, perhaps (6) ORIENT [DD]
11 Space made for one to introduce small eats (7) CANAPES {SPACE}* over {AN}
16 Politician twice rejected as China grass (4-4) AGAR-AGAR {RAGA}{RAGA}<=
19 Repel Somalia's savage attack, somewhat (6) ASSAIL [T<=]
20 Daily wearing dress — a feature of Chinese ceremonial dance (6) DRAGON {D{RAG}ON}
23 Loving the action on first of May (4) WARM {WAR}{May}
Reference List
On = BY, Religious = PI, Dead = D, Years = Y, Small = S, Daily = RAG