In spite of being set some 3 weeks after the infection, some vehicles still have their lights on.
Shotguns do not fire tracer rounds.
The chain on the chainsaw only moves when you are attacking with it. It should be moving all the time.
The assault rifles have 30mround magazines, yet can hold 50 rounds.
Since rifle scopes are mounted atop rifles, tracer rounds should come from beneath the scope. In the game, they can be seen coming from the side.