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There are coins on the road to collect. Whilst driving on the road, all the other cars are seen driving straight through the coins.
In the underwater levels of the game, Crash is able to access a submarine to navigate the depths and finish the level. One of the abilities of the sub is that you can shoot torpedoes to kill enemies and continue to the end of the level. If you turn the sub towards you so that the sub and Crash are facing the screen, you can see that there is no muzzle for the torpedoes to shoot out of (the torpedoes fire from the center of the sub).
No matter what weapon you are holding before a cut scene appears, the cut scene will always show a pistol, even if you were holding a rifle.
Not a mistake with the game but a mistake with the booklet. In the "History" section, it says Chris and Jill defeated T.A.L.O.S. in 2002, when in the game, and in RE: The Umbrella Chronicles, it's established that they defeated him in 2003.
When Cloud and Aerith visit the first 'Sephiroth clone', in Sector 5 in Midgar, she says to him "This guy are sick". That is a translation error and should say "This guy is sick".