(Please post comments on ONLY the picture quiz hereinbelow. To post comments on the crossword puzzle, please click here.) Quite a straightforward puzzle. Thanks to Phssthpok. Definitions are underlined in the clues.
Across
1 Lured to island while asleep? (6)
BAITED : AIT(a small island, especially in a river) [ contained in(in) BED ](while asleep).
5 Dictator is French – not person from Eastern Europe at heart (8)
NAPOLEON : NON(French for “not”) containing(… at heart) [A + POLE(a person from Eastern Europe) ].
9 Boycotts infra-red dissection of Scottish children (6)
BAIRNS : BANS(boycotts;rejects) containing(… dissection) IR(abbrev. for “infra-red”).
10 African country next to Niger lacking one loaf (8)
MALINGER : MALI(an African country) plus(next to) “Niger” minus(lacking) “I”(Roman numeral for “one”).
Defn: To avoid work by pretending or exaggerating illness or other incapacity.
11 Rebellion by one South African party divided four consecutive notes (8)
DEFIANCE : [ I(Roman numeral for “one”) + ANC(abbrev. for the African National Congress, the South African political party) ] contained in(… divided) D,E,F,E(four consecutive notes in the diatonic musical scale). Is that a typo for “dividing”?
12 A kid is comfortable (2,4)
AT EASE : A + TEASE(to kid;to make mock playfully).
13 Jack goes for a walk (4)
HIKE : Double defn: 1st: To raise, especially abruptly, eg. prices of goods.
15 Smiles after tea disappoints (8)
CHAGRINS : GRINS(broad smiles) placed after(after, in an across clue) CHA(tea, from the Mandarin name).
18 He worked out Scuba: not British, but had energy (8)
COUSTEAU : Anagram of(worked) [OUT + “Scuba ” minus(not) “b”(abbrev. for “British”) plus(but had) E(abbrev. for “energy” in physics) ].
Answer: Jacques, French oceanographer who co-developed the Aqua-Lung, the original name of the SCUBA (self-contained underwater breathing apparatus). And of course he was a regular user of it during his work studying the sea and all forms of marine life. A WIWD (wordplay intertwined with definition) clue.
19 “Excuse me, what did you say?” written back in the morning (4)
AHEM : Reversal of(written back) EH?(a terse way of asking “what did you say?”) contained in(in) AM(the morning, from “ante meridiem”, Latin for “before noon”).
Answer: An interjection to attract someone’s attention.
21 Solid copper globe injected into two hearts, for example (6)
CUBOID : CU(chemical symbol for the element copper) + [ O(letter that looks like a 2-dimensional globe) contained in(injected into) BID(in some card games, eg. bridge, a declaration of how many tricks one expects to make, an example of which is “two hearts”) ].
23 City in California favourite to occupy (4,4)
CAPE TOWN : CA(abbrev. for the state of California) + PET(a favourite) + OWN(to occupy;to take possession and control of).
25 Singers and actors: only half rational (8)
CASTRATI : CAST(collectively, the actors in a play or film) + the 1st 4 letters(only half) “rational “.
Answer: Male singers who have been castrated before puberty so as to retain their soprano or alto voices.

26 Fragment from particle ricochets into minister (6)
CLERIC : Hidden in(Fragment from) “particle ricochets “.
Defn: … performing religious functions.
27 Pick up small potatoes, pea soup and trifle (8)
PETTIFOG : Homophone of (Pick up) “petty”( trifles;in slang, small potatoes) + FOG(which if dense, is called “pea soup”).
Answer: Used only as a verb, to quibble or fuss over trifles.
28 Yield to success usually (6)
SOFTEN : S(abbrev. for “success”) + OFTEN(usually;routinely).
Defn: To relent, to give in under pressure or influence.
Down
2 Saw Bill get older (5)
ADAGE : AD(short for an advertisement in the form of a promotional bill;a pamphlet) + AGE(to get older).
Defn: A wise saying.
3 It’s snared wild sloth (9)
TARDINESS : Anagram of(wild) IT’S SNARED.
4 Dispensing with request for lullaby? (6)
DOSING : [DO SING](please sing, a request for a lullaby, say).
5 Calculation might make me burn (6-9)
NUMBER CRUNCHING : Anagram of(… CRUNCHING) NUMBER =( might make) ME BURN. A reverse clue where the answer gives a wordplay for the clue’s wordplay.
6 In reverse, push here to retreat (4,4)
PULL AWAY : PULL(the opposite;in reverse of “push”) + AWAY(the opposite of;in reverse of “here”, as in “he’s not here, but is away”).
7 Stab organ with end of knife (5)
LUNGE : LUNG(the respiratory organ) plus(with) the last letter of(end of) “knife “.

8 Deference to honour is found by Anglican church (9)
OBEISANCE : OBE(abbrev. for “The Most Excellent Order of the British Empire”, an honour bestowed by the British monarch) + IS plus(found by) AN + CE(abbrev. for the Anglican Church of England).
14 Imbue a clue into puzzle (9)
INOCULATE : Anagram of(… puzzle) A CLUE INTO.
Defn: To influence, say, with ideas or opinions.
16 Joint abuse attracts complaint (5-4)
ROAST-BEEF : ROAST(to criticise severely, perhaps to the point of abuse) plus(attracts) BEEF(slang for a complaint).
17 Star is embarrassed and grumpy, perhaps (3,5)
RED DWARF : RED(embarrassed, from the colour of your complexion when you are) + DWARF(an example being;perhaps is Grumpy, one of the seven dwarves living with Snow White in the fairy tale).
Answer: A small and relatively cool star (no, Dudley Moore is not an example).
20 Adds piquancy when CIA gets caught (6)
SPICES : SPIES(the CIA’s personnel) containing(gets) C(abbrev. for “caught” in cricket).
22 Leaders of orchestra conduct offensive musicians (5)
OCTET : The 1st letters, respectively, of(Leaders of) “orchestra conduct ” + TET(the military offensive by North Vietnam during the Vietnam War).
Defn: … in a group of eight.
24 Surrender to sound of the sea? (5)
WAIVE : Homophone of(sound of) “wave”(the sea, usually as “the waves”).
Answer: To give up voluntarily, eg. a claim, or a right.
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The following pictures have unidentified links to the puzzle.

(Please post comments on ONLY the picture quiz hereinbelow. To post comments on the crossword puzzle, please click here.)
The carbon atom in methane has an OCTET of electrons, possibly?
Pic 5 – John Denver sang Calypso which was a tribute to COUSTEAU.
Right muffin and grandpuzzler:
Pic3: Illustrates the OCTET rule in chemistry, where atoms tend combine to share 8 electrons in each of their valence shells. So the hydrogen atoms as well as the carbon in CH4 each share an octet of electrons.
Pic5: The John Denver song was a tribute to COUSTEAU and his ship, the Calypso.
Answers to the rest:
Pic1: The CUBOID is a bone in your foot.
Pic2: A West Indian steel band playing calypso music.
Pic4: George Orwell, second from right standing (at the BBC), created NAPOLEON the pig leader in Animal Farm.
Pic6: A purse made of a type of leather, shagreen, from the French “CHAGRIN”.