When the train is attacked, the attackers come from the right of the train. But the bullet holes in the woodwork inside the train show that the shots came from the left.
In the cattle stampede scene, the night sky is much darker above the wagon train camp than where the cattle started stampeding.
This film is set in 1875-6. The real-life Fort Worth Star newspaper would not be founded until 1906. It would combine with the Fort Worth Telegram to become the Star-Telegram, and it still published as of 2022.
In the opening sequence, the shot from inside the printer's wagon showed a plain blue background behind the driver, with no trees or clouds or anything, not even dust. It was obviously done in the studio.
At about the 12 minute mark as the camera pulls away from Randolph Scott's hand holding a knife a shadow moves over Scott.