I tried the plugin with L4D2, and I got the following errors:
Colorize: No colorization, and error message, "Native GetEntDataEnt2 reported: Offset -1 is invalid"
Set alpha: No effect, and error message, "Native GetEntDataEnt2 reported: Offset -1 is invalid"
Invisible player: No invisibility, and error message, "Native GetEntDataEnt2 reported: Offset -1 is invalid"
Disco mode: No disco, and constant error messages "Native GetEntDataEnt2 reported: Offset -1 is invalid"
Invisible player only: No way to turn it off
Explode: No explosion.
EDIT:
This probably works better