Continuity mistake: When the lottery winner is going to die, the beer bottle he takes out of the fridge moves all over the place. It even vanishes a couple of times.
Continuity mistake: When Evan comes into the flat and walks towards the window, pay attention to the sink, there is a red cup or something in it. However when his arm gets stuck in it, there is nothing red in the sink, and there was no time for him to take anything out of the sink.
Revealing mistake: When the camera shows the coffee cup in the cop's car, you can see the ignition is in the off position. (00:09:16)
Revealing mistake: When the coffee cup tips over onto Officer Burke's lap, you can see the device that was making it vibrate. (00:10:04)
Revealing mistake: When Nora's son gets killed, we can see the boy under the falling piece of glass. But in the shot where this piece is just about to smash him, you can see on the DVD edition that there is a dummy instead of him because his arms are too long relatively to the whole body and also the hands are obviously not human. (00:41:20)
Chosen answer: Eugene's death had no clues I know of, but Clear and Rory's did, Rory's clue was with Nora's. The trophy's shadow is segmented, giving it a divided look, Rory ends up divided to pieces by the barbed fence. As for Clear, Bludworth hints at it with his comment "such fire you have now".