heres what you do.
have 2 lights in a room, the red one and lets just say a white one. give the 2 lights the same name, lets say Light1. and make sure the lights are dynamic, not static!
leave the white lights fpi scripts the same, but change the 'start' fpi script of the red light to the 'lightoff' script found in your script bank.
now set up a triggerzone so you walk into it right as you enter the room. in the triggerzone, put your lights' name 'Light1' in the 'If Used' box. and change the Main Script to the 'plrinzoneactivateused' script found in your script bank.
if done correctly and i understand what you were asking correctly you should get the result you were searching for
cheers!