Revealing mistake: As the miners are trying to break down the washroom door, the camera pans over the door frame from Rose's side to the miners' side. Just as it settles into its final position, you can see the sliding wall section they used to allow the camera to pan, sliding back into position on the left of the doorframe.
Revealing mistake: When Christopher first meets Officer Gucci on the bridge, it is absolutely pouring down rain on and around them. However the river which they are just a few feet from is calm and not being rained on. I know that rain has to stop at some point, but they are on a bridge and no rain is hitting the water below the bridge.