Continuity mistake: When Wanda arrives at Archie's office, there are piles of papers/books on the mantel beside the door, stacks of papers/books, a lamp and draperies behind Archie. During Wanda's visit, things behind Archie change, disappear, then reappear, the lamp changes the direction it points, the draperies change, and part of the piles on the mantel change entirely.
Continuity mistake: When Otto forces Archie into the oil barrel, you see in the distance Ken driving the steam roller. In the next camera angle, you see a closeup of Ken running over a wheelbarrel which is next to a cargo unit. The problem is that the wheelbarrel was nowhere to be seen in the previous scene and neither was the cargo unit. (01:40:40)
Continuity mistake: When Otto is putting the french fries (chips) in Ken's nose, he puts the second one in his nose and then you see him chewing. The problem is that he didn't have anything in his mouth because he was asking Ken questions right before he put the second one in his nose. (01:22:56)