The cover for the circuit breaker box that Batman uses in the derelict building reads "DANGER Electricty," misspelling electricity in both frames in which it is seen.
When Gordon is on the motorcycle chasing the car, he uses his right hand to fire his handgun. A motorcycle's throttle is on the right side, so taking his hand off to shoot would have forced the bike to slow down.
The electrical service hatch set in the floor of the building reads "80,000 WATTS." Electricity is typically measured in voltage, not wattage.
Propane tanks do not explode instantaneously upon being hit by bullets. In the open air, they do not explode at all unless they first cook for some time in a fire before they rupture. This is called a BLEVE which stands for boiling liquid expanding vapor explosion.
The actor playing Bruce Wayne doesn't even bother to change his voice. The actor uses the same voice to portray both Bruce Wayne and Batman, and it's very noticeable but it could also give away his identity. He doesn't even bother to use a voice enhancer, and just plays it straight. Not a great voice performance at all.
Why does Gordon strip Flass naked??? This is makes no sense, as Gordon is not only a cop, but he leaves fingerprints on Flass clothes. Even if this takes place with the original graphic novel did, this still leaves evidence behind and is something a cop just wouldn't do.