Continuity mistake: When Alice knocks over the giant Licker in the Rolls-Royce, the driver's side of the car remains completely undamaged. Unlikely, but for the rest of the chase there are four giant scratches across the rear of the car. (00:51:10 - 00:52:05)
Revealing mistake: When we see the Kremlin in the Rolls Royce chase, there is an overhead shot of the car skidding with tyre marks in front of the car from previous takes. (00:51:10)
Continuity mistake: When the car comes to a stop after killing the licker, the front wheels are straight and flush with the body of the car. When the camera changes the wheels are turned over to the left and sticking out. (00:52:20)
Continuity mistake: When the Rolls Royce jumps through the yellow van, the Spirit of Ecstacy (the emblem of Rolls Royce) breaks off, but at the end of the chase, it's still in place. (00:52:55 - 00:55:50)
Continuity mistake: Outside of the corridor of light sequence, nobody ever seems to run out of ammo, or bother to reload, most notably Ada and Alice.
Factual error: Semi-automatic guns don't just click empty, like they do in a lot of movies. The slide would lock back until you manually cock the gun. Yet in the corridor of light scene, this is exactly what happens: Alice's gun just clicks when it's empty.
Continuity mistake: In the scene when Ada Wong walks into the Umbrella control room and kills all the agents, she stands in the middle of the room. She uses a gun to kill all the agents, who are sitting behind glass computers. In that scene, and in later shots, we can see that the glass is intact and has no bullet holes in it.
Continuity mistake: The Rolls-Royce constantly goes from being bulletproof, to not being armored at all.
Continuity mistake: Ada Wong seems to never run out of ammo. She never reloads and she doesn't carry any magazines with her. Alice's Kriss Vectors should only hold 13-33 rounds but she fires more than the rounds. She doesn't hold any mags.
Revealing mistake: When Alice shoots the zombie in the blue dress, we get a frontal shot of the gun. Pay close attention to her trigger finger: it doesn't move at all, while the gun does fire.
Other mistake: When Alice pushes in the new magazine, she doesn't pull back on the slide, meaning the gun doesn't have a new bullet in the chamber, thus is unable to shoot.
Factual error: Rain injects herself with the Las Plagas parasite, which seems to take the form of a little scorpion. Little or not, it's not small enough to be pushed through an injection needle.
Factual error: Typhoon-class submarines have a crew of 163 men. It is impossible for Jill Valentine to operate a submarine on her own, even with help from Rain.
Continuity mistake: At one point during the chase, a zombie pulls up and shoots the driver side window, during an inside shot. The shot then briefly cuts back outside, and look closely: the driver side window is still there.
Chosen answer: Jill was unconscious at the time, while Claire was awake, therefore the loss of memory may differ by state of mind, or vary from person to person.