In the beginning of the game, when the African Soldier stops Chris and Sheva to check for their papers, he has his AK out but, in the next scene, it is on his back a second later.
When Chris and Sheva need to break down the door only to find DeChant and Alpha Team dead, it shows both Chris and Sheva breaking the door down, but in the cut scene only Chris is breaking down the door with Sheva right behind him.
If a player character fires a weapon in the cutscenes, the ammunition level stays the same.
In Chapter 4-1, as a tunnel is collapsing all around and both play characters are running, they make a dive for the descending door twice.
The Gatling Gun is incorrect in this game, in real life, the GG is a hand crack gun that it attached to a turret of some kind. In the game, it's a Mini Gun that runs off a battery.
An RPG-7 is shown being fired from a helicopter. Since the RPG-7 produces considerable backblast, it would be extremely perilous to fire one from a helicopter.
Some weapons start out with much less ammunition than they would usually have. The Beretta 92FS pistol, for example, can carry 15 rounds, but can only carry 10 in-game.
The RPG-7 is technically NOT a rocket launcher because a rocket launcher fires a rocket designed for that launcher, the RPG series are grenades, modified to be fired. However it is plausible to say that Capcom called it that because that is what most people call it.
During the cut-scene at the beginning of Chapter 4-1, the BSAA patch on Chris' shoulder does correctly say BSAA, but the full name and North America are spelled out in reverse, e.g. aciremA htroN.
Chapter 2:1 Storage Facility, after the first encounter with the Kipepeo flying parasites the water in the tunnel behind the locked door is flowing up the slope towards you instead of downwards.
Spelling and grammar errors in subtitles.
When Chris and Sheva reach the part of the cave with the flowers, Chris states that no one has been there for a while. The powered-on electric lights would suggest to the contrary.
Nonhuman enemies can drop items, even though there is no reason for them to carry them.
Chris and Sheva were never given the orders to retreat, what actually happen is that they decided to flee but changed there mind once Chris decided to locate Jill. Yet, all the characters act as if they got those orders to do it. This means that either Capcom overlooked this mistake or cut out a section of the game that explains this.
Sheva calls Wesker's ship a tanker. It is, in fact, a cargo ship.