Berlin Main Station opened in June 2006, the building took more than 10 years. Before this. Trains only passed through the station, but did not stop there. So, Justin Quayle cannot have arrived at Berlin Main Station in 2004, when the movie is set, as it is implied. Also, long distance trains only stop underground. The tracks above ground are reserved only for regional trains.
When the turbo prop plane is making a drop into the village, the two pilots push the yoke forward. That would cause the plane to pitch down, however, the plane is clearly climbing when the drop is made.
At the pedestrian crossing in Germany, Justin and Birgit are menaced by two people on a motorcycle. It passes closely by, but then turns sharply 180 degrees to the left, in order to take a second pass at the pedestrians. The camera cuts to a reflection in a car window of the motorcycle turning, but in the mirror image the bike is still turning to the left. The camera pans to the real motorcycle, which is now turning sharply to the right.
When Quayle shows the fake ID to the German police officer in Berlin, it is a Dutch passport. However, when he pockets the document again, it is shown to have a blue cover. Dutch passports have a red cover.
When Tessa is videochatting (under Windows XP) the FFWD/REW controls are clearly visible in the interface. Above the video a text can be read "Buffering 500 mbps", a speed which is impossible to achieve on most lines, especially the consumer-grade connection that the German activist is using.