When Laura enters Room T405, from the outside the door is on a corner, yet from the inside the door is in the center of a long wall.
Mildred enters the church and says her first line by the door. Less than a second later she says her second line standing in front of steele by the altar.
When Laura jumps on Keyes at the end of a foot chase, they land in a mud puddle. We first see Laura with her hair fully coated in mud and water. In the next shot, her hair is dry.