At approx. 27 mins, Vera and Billy go to the beach to find Phillip. He is there, wearing black shorts, but in the next shot appears to be naked-with no time to have taken off his shorts.
When Anne goes to take a cup of tea to Rick and finds him hanged she drops the cup and it smashes all over the floor with the contents. When Vera enters the room there is no sign of the spillage.
When Rick arrives at the cottage, he stops his BMW right in front of the door and is seen unloading liquor from the boot. He carries the liquor into the house and the front door closes. The BMW is not seen again - not in the same place, not parked round the side, not in the village, not accounted-for in the script - even though, for a suspicious death, the car in which the victim arrived would be considered a source of important evidence.
Vera tells Aiden Healy that he will need to drive her car. "Go easy on the clutch," she warns him. However internal views of the Land Rover in other episodes have shown that it has automatic transmission so it does not have a clutch.
When Vera arrives on the island, she has taken the boat because, as she says earlier, the tide is in and the causeway is impassable. As she steps off the boat at the mole, the beach alongside clearly indicates a condition of a very low tide.