When McIntire is captured and returned to the Union Army, the soldier on the right (who is holding him at gunpoint) is using an old relic rifle which is missing a hammer, thus it is not capable of firing.
The location of the cellar of the burned house is very different to that of the house prior to the burning - different trees and vegetation and topography.
A shot of a column of Union soldiers marching near the end of the film has obviously been superimposed on a background, along with smoke representing cannons.