Revealing mistake: The paint in the "we did it" lettering in the roaring bear scene runs "downwards," according to the camera position, not according to the vertical of the shot buildings. (01:51:15)
Suggested correction: While yes there are slight angles involved, considering this was most likely a physical prop on-set, the direction of the camera tilt wouldn't be a factor. The direction the paint runs in doesn't seem wildly inconsistent with what would happen when painting something like that.
Revealing mistake: When Dr. Railly is tied to the bed in the motel, her bonds are not very secure. In her struggles, she very nearly frees her right foot, by accident.