Throughout the game, the colors of the horse the characters are riding are different than the horses they're riding in the cut-scenes.
On the bridge cut scene when Pat Denton and Cole are ambushed by Quick killer, Cole draws his pistol but when he walk past the camera it still shows it in the holster.
The Ned's Ferguson rifle has some kind of cloth wrapped around its barrel. But when a player aims with the rifle, the cloth is gone.
The Volcanic 10 is a lever action pistol but the game depicts it to fire like a revolver.
When Clay and Colton are on the train going to the mining fort, they begin to shovel coal into the furnace to make the train go faster. They dig their shovels into were the coal is, the sound of coal getting scooped is heard, yet when they move the shovel from the coal holder to the furnace, there is not one bit of coal on the shovels.
Neds Ferguson rifle appears to fire a cartridge yet in reality the Ferguson was a breach loader that fired a round ball.
When Colton asks Honest Tom how to go to Dodge City, he is told it's one day far, but when he travels there later, it's just a few moments away on horseback.
One of the guns in the game is a 1887 Winchester lever action shotgun. The game takes place in 1880. The gun wasn't invented yet.It is also depicted as a single barrel shotgun rather then a lever action.
One of the Rifles used in the game is a Winchester high wall. The game is set in 1880 and the high wall didn't come out until 1885. Also all of the powder kegs are listed as black powder, gun powered wouldn't have been called that until the early 1890s when smokeless powder was popular.
One of the mini games played in the Saloon is Texes Hold em. The game is set in 1880, Texas holdem wasn't played until 1900.
It is never explained exactly how Magruder lost Coranados cross after he had his eye shot out. One would think he would have been able to retrieve it.
After Reed's death, Magruder orders his bodyguard to put a price on Colton's head. However, Colton is never attacked by bounty-hunters or mercenaries, not even from this point on (just the regulars bandits).
Assuming Colton was born in either 1863 or 1864 he would be 16 or 17 years old in 1880 when the game takes place. But he looks more like a man in his 30s rather than a teenager.