Factual error: When the zombies are about to over-run the house, one of the ravers sacrifices himself by shooting a keg of gunpowder to blow up the building. The problem is that gunpowder is not an impact explosive, you could shoot that keg all day and all it would do is put holes in it. Just shooting it would not cause an explosion.
Factual error: Within minutes of encountering the dead, the survivors are handed out guns and artillery and immediately know how to use them without any training. Considering the size and caliber of some of the guns they use, I doubt they would be so proficient, or calm, after less than a few minutes of using guns.
Factual error: When shooting several zombies approaching his boat, Captain Victor Kirk uses a Desert Eagle pistol and fires 13 times in a row without reloading - a Desert Eagle clip can hold only 7 to 9 rounds, depending on the caliber.
Visible crew/equipment: When Cynthia is shot by Casper, the impact sends her flying. If you look closely you can see a harness under her skirt and over her shoulders (under her blouse).
Continuity mistake: Kirk leaves his ship and appears on land shooting at the zombies in the water. Yet he is not wet at all.
Continuity mistake: When the characters are shown in bullet time in the long shootout scene, they are all wearing different clothes than in the previous normal time scenes.
Continuity mistake: When the swimmer girl is walking through the forest looking for her missing boyfriend, at first she is only wearing her thong. In the next shot of her, she's wearing all the clothes she had on before she jumped in the water.
Other mistake: The entire time Captain Kirk is on the boat in the pouring rain he only gets a drop, maybe 2, of rain on him.
Continuity mistake: The guy who gets sprayed with acid in the face is holding a bandage on it shortly after getting sprayed and has a silver watch visible. The shot jumps from him to some one else and then back, where he has no watch visible, then back to some one else then back to him with his watch back but sleeve covering part of it.
Continuity mistake: When Simon has been covered in acid, he is leaning against a tree, and in one shot we can see Liberty standing up. But in the next shot she is kneeling down, and then in the next standing up again.
Other mistake: When the three rave survivors are hiding in the house, they don't even barricade the door. Alicia just opens the door and walks right in. You'd think they would have at least but the wood across the door like later in the film.