Countdown on the bomb jumps back a few seconds with every camera change. At 36 seconds, the timer begins to skip a few seconds with each change. At 8 seconds, it suddenly reverts to 29 seconds for a few seconds, then continues on at 4 seconds.
In the opening minutes where David Keith is shown working at the rear of his broken down early model rear engine Volkswagen Beetle, a cloud of steam surrounds him to indicate a problem of an overheated engine. The engine in this model of Volkswagen Beetle is air cooled, thus there is no water for the engine to produce steam with.
The military vehicles, including jets,have no national or department (i.e. army, etc) name/insignia, nor unit ID numbers.
In the 57th minute Mr. Hudson asks the Chinese Ambassador Po for a fortune cookie. Fortune cookies are a US (San Fransisco), not Chinese, creation.
After being lightly struck by the Mexican's gun, Mason is sent sent flying as if he was pistol whipped. He was lightly hit under the chin after the gun was held to his temple. This may have hurt but would not have sent him flying and not likely result in a cut to the forehead.
After being pistol whipped, Mason is picked up by a helicopter. In the next scene two helicopters are turning away from a military plane in flight and on which Mason is a passenger. The implication is that the helicopter has transferred him to the plane, but this is in fact would be extremely dangerous and unfathomable.
The jeep which transports Mason reads MILITARY POLICE. It has no country designation nor unit ID number. It's also unlikely he would be transported in a military police (MP) vehicle, rather than any other army vehicle.
The opening scenes are supposed to be happening in Dresden, Germany, but there are a few recognizable landmarks from Sofia, Bulgaria, the writings on the streets are in Bulgarian ('Chistota' on the thrash containers), the cars are with registration plates from Sofia, Bulgaria.