Object not set to a reference(again)

Apologies for this. I know doing a != and == probably is probably open to critism but im still at the early learning stages.

I have two very basic scripts and both were working until I inserted the != part and associated var's. Can you help me pinpoint what is wrong?

robo-istat.js

 #pragma strict
 var powerup : robo_powerup;
 var Start_Player_Agility = 10;
 var Start_Player_Weight = 100;
 var Start_Player_Speed = 100;
 var Start_Jump_Speed = 2;
 var chMotor : CharacterMotor;
 var player: Transform;
 
 
 function Start () {
 
 chMotor = GetComponent(CharacterMotor);
 powerup = GetComponent(robo_powerup);
 }
 function Update () {
 
 if (powerup.triggered == true)
 { chMotor.movement.maxForwardSpeed = 1;
  print("Super Slow"); 
 }
 if (powerup.triggered != true)
 { chMotor.movement.maxForwardSpeed = Start_Player_Speed;
  print ("Normal speed");
 }
 
 
 }

Then my second script - robo_powerup.js

 #pragma strict
 var destroyedpowerup : GameObject; // Declare the object to be destroyed
 var target : Collider; //this is the variable that will hold the colliding object
 var triggered : boolean = false; //If we only want to detect the first time it's triggered
 
 
 function Start () {
 }
 
 function OnTriggerEnter(collision : Collider)
 {
 if (collision != target) //The colliding object isn't our object
 {
 return; //don't do anything if it's not our target
 }
 triggered = true;
 print("This worked");
 Destroy(destroyedpowerup);
  
 // Print - to debug testing
 // Destroy sphere
 
 }

Many thanks in advance :-)

[EDIT] Opps forgot the error - NullReferenceException: Object reference not set to an instance of an object robo-istat.Update () (at Assets/robo-istat.js:18) [/EDIT]