disable code when level is rendered

I'v probably told you before that i have to disable a script when my level is loaded but the problem is that i don't know what functions or lines of codes i have to use to get this to work. I want to disable a loading script when my "Random_Maze" is finished, my "Loading_Script" is: private var tileCounter = 0; var height:int = 12; var width:int = 12; var updateString: String = "";

 function UpdateProgress() {
     var progress:float = tileCounter/(height*width*6.0);
         updateString = progress.ToString("Loading: #0%"); 
         
 }
  
 function OnGUI(){
     GUI.Box (Rect (0, 0, 3000, 3000),updateString);
         GUI.Box (Rect (0, 0, 3000, 3000),updateString);
             GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                 GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                     GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                         GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                             GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                                 GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                                     GUI.Box (Rect (0, 0, 3000, 3000),updateString);
                                         GUI.Box (Rect (Screen.width /2 - 100 ,Screen.height /2 - 0,200,50),updateString );
                                         
 }

can i put like

 if (progress.ToString("Loading: 100%")){
 script.Loading_Script.isDone
 }

or something like that?