Poor color-matching and obviously differing filming locations between Chinese and Thai footage that has been edited together.
The same railings in the Chinese inn are knocked down multiple times.
Watch the opening carefully. One of the toughs has what appears to be an M-60 machine. That it's a replica is certain, since he holds the weapon up with one hand. When he fires it, it shoots, but there's no ammunition belt, and M-60's don't use a magazine.
During the Chinese sequences, most guns are obvious dummies or replicas fitted with tubular muzzle devices similar in appearance to silencers, into which ordinary firecrackers are inserted to simulate gunfire. In some shots, the undetonated firecrackers can be seen. (In the Thai footage, the actors appear to be using real guns with proper blanks.)
When the android uses his gun as a flamethrower, it is obvious that the effect was achieved with a rope that has been saturated with a flammable substance and set ablaze.
The arms of "Peter" the hopping vampire grow noticeably longer when he shoots fireballs from his hands, presumably to conceal the fireworks that the stuntman is holding.
Obvious dummies in almost all instances of characters falling from significant height.
Obvious dummies when the machine-gun nests at the enemy compound are blown up.
Dialogue is very poorly looped throughout, with little or no apparent effort to make the dialogue match the actors' lip movements, and with some characters' voices varying in different scenes.
The motor sounds are poorly synchronized with the leg movements of the android.
The android's gun kills vampires even though none of the other characters' guns have any apparent effect on them. This is never explained.