Factual error: In the underwater scene when Rex blows up the ice pack, ice appears to be denser than water in this situation. The ice sinks when it's blown up, and even if there were pieces of metal on top of the ice, it shouldn't. Some pieces the size of a five-story building have no metal and still sink. (01:43:00)
Factual error: During the chase in Paris, the bad guy's car is nicked by the metro train. Instead of lunging forward (in the train's direction - and left in the car's direction) the car jumps 20 meters into the air. Even though the train has a tilting front end, the impact would never create a force in that direction. (01:00:30)
Factual error: During the chase scene through Paris, they start by driving through the Arc de Triomphe which is North West from Central Paris. Then the next scene the chase takes us by Notre Dame, where it is on the other side of town, North East. The Eiffel tower is on the west side of town. So, started at the North West, drove to North East of town, then drove back to West near the Eiffel. They could have just driven south of Arc De Triomphe and be there in something like 10 minutes.