Continuity mistake: At the very end of the film. When the 3 helicopters and the seaplane come into land, it is quite a wide shot, with no boats visible. A few minutes later, when the seaplane takes off again, a big white boat is near the coast. Even if the boat was off camera during the landing scene, a few minutes was surely not enough to get that far, and that close to the shore.
Continuity mistake: When Arnold lets go of the landing gear he lands in the water. A few seconds later we see him walking up towards the beach, and we can now see that he is only wet from his waist down. It's not likely that he would have been able to land standing on his feet and not not becoming completely soaked.
Continuity mistake: Rae fires a rocket at the police van, first she fires it back to front then the second time she fires it correctly only this time she is knocked back by the recoil, why wasn't she affected the first time and pushed forward? Also there should be no recoil with a rocket launch.
Continuity mistake: When Matrix first rips out the seat of Cindy's car and sits in its spot, his body sits very low to the the bottom of the car. You can even see in the next scene that his head is clearly lower than Cindy's. However, during the chase scene, his head is level with Cindy's.
Continuity mistake: When Matrix first abducts Cindy and is talking to her in the car, both of their windows are rolled up. When she backs the car out, the passenger side window is rolled down. In the next shot, as they exit the parking garage and pay the attendant, both windows are rolled down.