The Rex Montana Story - S1-E35
Revealing mistake: When Flint follows the Indians, there's a strong wind blowing. But the two puffy clouds in the backdrop sky never move.
The Case of the Lucky Loser - S2-E2
Visible crew/equipment: After leaving her husband at train station, Harriet takes a cab to meet a man at a cabin. After a few mins, she takes the man's car to go home. As she drives away, there's a reflection of a man, in suit with glasses (possibly the director) standing offscreen. (00:05:20)
Visible crew/equipment: Diamond parks outside the apartment house, and when he opens the car door, it mirrors several stage lights and reflectors.