The Furnace Flats Affair - S1-E22
Factual error: April finds that the sign pointing to Furnace Flats has fallen off the signpost. But the board she picks up is perfectly smooth, with no nails or nail holes in it anywhere. It's never been attached to anything. (00:00:50)
The Furnace Flats Affair - S1-E22
Revealing mistake: Stock footage spliced in at different points during the desert chase scene increases the size of the posse threefold, and changes the terrain completely from one shot to the next. (00:15:00)
The Furnace Flats Affair - S1-E22
Continuity mistake: The smudges on April's face as she treks through the desert keep changing shape and position between takes. (00:26:40)
The Furnace Flats Affair - S1-E22
Continuity mistake: From the inside, the swinging saloon doors are completely intact. From the outside, they're missing several slats. Later, the same doors have breaks that change positions constantly between shots. (00:02:10)