The scene where the huge bell falls revealing Jaa with the drum sticks, the next scene when the wushu fighter approaches Jaa, the bell is gone.
Kham destroys the street lamp and his jacket is turned to the other side, but in the very next shot it's normal.
In the second fight with Johnny the amount of tightrope on Kham's hand varies from shot to shot.
During the bone-breaking scene, Kham forces one of his foes into the splits by pushing the guy's leg up towards his body while upright. However, when the foe in question does his initial kick he does it with his right leg, then there's a cut and it's his left leg that Kham forces upwards.
At the end, when madame Rose lifts up with the helicopter, the landing site is clear of people, though in the previous and next scenes there were characters at the big "H" mark.
In the long-take brothel fight, Kham knocks a thug's head into a frame and glass shatters. However, the shattering glass is a CG effect and the reflection on the glass is still there. (This is due to an on-set mistake when the prop failed to break)
During the warehouse fight, when Jaa fights a bunch of Johnny's goons he does the back-flip into a handstand, to avoid the dirt bike. You can clearly see the supposed brick wall move behind him, when Jaa bounces off it.
During the bone-breaking scene, if you look carefully at those whose arms are broken, the hands are the wrong way around, so the elbow was actually bending normally. This is particularly apparent when Tony Jaa uses his knee on one guy's arm to break it.
During the final fights were Tony Jaa is attacked by hordes of people you can see that the same footage is used over and over, only from different sides. Because people that are defeated in the beginning can be recognized later in the running scenes.
In the bone breaking scene, Jaa fights the same man thrice in the sequence - at the start, the middle and the end.