Across
The last sign of resistance (5)
I haven't cracked this one yet — but Fifteensquared have:
Double definition. Omega is the last letter of the Greek alphabet, hence “the last” of anything; and the standard abbreviation for ohms, the unit of electrical resistance, is the capital-letter Omega, .
Swimming every gala in a mediocre fashion (9)
He corrects each misdirected flyer (9)
Still upset? Not very (5)
I haven't cracked this one yet — but Fifteensquared have:
IN [v] ERT (as a verb = turn upside down = upset), without the V (very).
Hold up back of trousers with belt or elastic (7)
I haven't cracked this one yet — but Fifteensquared have:
Anagram (elastic = flexible) of the last letter (back) of [trouser] S + BELT OR .
What buds do sometimes on vacation in Orlando? (7)
I haven't cracked this one yet — but Fifteensquared have:
S [ometime] S (on vacation = after emptying), in BLOOM (the actor Orlando Bloom ).
Butchered animal and left out membranes (5)
I haven't cracked this one yet — but Fifteensquared have:
Anagram (butchered) of ANIMA [l], without the L (left). Plural of amnion, the membrane that surrounds an embryo; I didn’t know the word, but I had heard of amniotic fluid so it was straightforward to deduce.
Light-headed (3)
I haven't cracked this one yet — but Fifteensquared have:
Double definition. Abbreviation for Light-Emitting Diode; or headed (as a verb) = was the leader of = led.
Snoops around Hooters (5)
I haven't cracked this one yet — but Fifteensquared have:
Double definition. Snoop = nose around = to be inquisitive; or hooter = slang for nose. (The surface suggests the US restaurant chain Hooters, whose name derives from a rather more vulgar slang usage of the word – though they will try to tell you it’s all about owls.)
Sport featuring Raider and a naughty kid jumping around (7)
I haven't cracked this one yet — but Fifteensquared have:
A + BAD (naughty), with an anagram (jumping) of KID around it. Team sport in which a player acts as a “raider” into the opposition’s territory.
Dorian dashed back inside store for cereal (7)
I haven't cracked this one yet — but Fifteensquared have:
GRAY ( Dorian Gray , as in Oscar Wilde’s novel) with RAN (dashed) reversed (back) inside.
Cover for bishop's joint (5)
I haven't cracked this one yet — but Fifteensquared have:
Double definition. A ceremonial hat worn by a bishop; or a joint, typically in woodworking, used where two straight pieces meet at an angle.
Once again insist on some sunscreen for cellulite (2-7)
To struggle against associate taking criminal cut (9)
I haven't cracked this one yet — but Fifteensquared have:
RELATE (associate, as a verb), containing an anagram (criminal) of CUT . To show resistance to something; a rather obscure word, but guessable from its derivative “reluctant” which seems to have survived better.
Arouse with a stiff bash? (5)
I haven't cracked this one yet — but Fifteensquared have:
A + WAKE (a party in honour of someone who has died = a bash for a stiff), with the question-mark indicating a rather contrived definition.
Down
Where solver can find a castle's boundary! (4)
I haven't cracked this one yet — but Fifteensquared have:
Double definition. Reference to 4d BALMORAL, where solvers of this puzzle can find a castle; or (in cricket) boundary = four = a ball hit to the boundary of the ground, scoring four runs.
Removing outer layers of eczema on nipple agitated old gasbag (8)
I haven't cracked this one yet — but Fifteensquared have:
[ec] ZE [ma] removing the two outer letters at each end (outer layers), then an anagram (agitated) of NIPPLE . People sometimes query whether “on” indicates a specific order for two wordplay elements, but it’s easier just to think of it as “next to”. Zeppelin = old airship, though strictly speaking it was a rigid structure containing lots of individual gasbags.
Overload current charging motor (4)
I haven't cracked this one yet — but Fifteensquared have:
TAX (overload = stress) + I (scientific symbol for electrical current). Taxi = a vehicle in which passengers pay a charge to travel, hence “charging motor”.
Scotch bonnet burns - remedy taken by mouth (8)
Nearly threw away page over writer's tip (3,3)
I haven't cracked this one yet — but Fifteensquared have:
BINNE [d] (threw away), without the last letter (nearly), then P (page), all reversed (over).
A frail icon rattling around Hollywood home (10)
Reported fees for American banks (6)
I haven't cracked this one yet — but Fifteensquared have:
Homophone (reported) of LEVIES (fees). US term for embankments along a river, especially to prevent flooding in low-lying areas.
Bulge spotted in Darcy's trousers (4)
Player left to go in second (5)
Exercising nude with active viewers (2,8)
Dim boy holds good degree (5)
Person involved in public relations regularly fell for bad lines (8)
I haven't cracked this one yet — but Fifteensquared have:
DOGGER (someone involved in sexual activities in a park or similar public place) + alternate letters (regularly) of [f] E [l] L . Bad poetry, written by someone who isn’t good at it.
Perhaps emergency exit leads to steel duct (8)
I haven't cracked this one yet — but Fifteensquared have:
First two letters (leads) of ST [eel], then AIRWAY (duct).
Parcel contains voided ticket for Waterloo? (6)
I haven't cracked this one yet — but Fifteensquared have:
BALE (a parcel), containing T [icke] T (voided = middle letters removed). Definition by example, indicated by the question mark.
Strategic gain from concrete situation? (6)
I haven't cracked this one yet — but Fifteensquared have:
Definition and cryptic definition. As in “make inroads into”; or a situation where you might find concrete is IN the ROAD.
See 29 Down
Plant a kiss on Frank Lampard initially (4)
I haven't cracked this one yet — but Fifteensquared have:
A + X (symbol for a kiss at the end of a written message), added to the initial letters of F [rank] L [ampard]. The plant that provides linen and linseed.
26d
(and 26 Down) Always veer off course, occasionally crossing motorway (8)
Type letters or click words in the clue