Continuity mistake: When Karl is at the Frosty Cream, in the shots of Karl there is absolutely no traffic on the street behind him. But in the shots of the Frosty Cream employee, look at the window to the left. A reflection of the street behind Karl shows a steady stream of traffic passing by.
Continuity mistake: When Karl stayed at the Warden's home, the first shot which would be the following morning, shows the exterior of a single story home. In the following shot of the interior, there is a staircase going up to a second floor.