Raycasting to make Buildings Clickable

I have a problem.

I used this code which I found somewhere here in the forums..it's a raycasting method for clicking objects.

` script ExecuteInEditMode

 var gSkin : GUISkin;
 var backdrop : Texture2D;
 var target1: Transform;
 var target2: Transform;
 private var isLoading = false;
 
 function OnGUI()
 {
  if (gSkin)
   GUI.skin  = gSkin;
  else
   Debug.Log("StartMenuGUI: GUI Skin object missing!");
  
 
 var backgroundStyle : GUIStyle = new GUIStyle();
 backgroundStyle.normal.background = backdrop;
 
 GUI.Label(Rect((Screen.width - (Screen.height *2)) *0.75,0,Screen.height *2,
 Screen.height ),"",backgroundStyle);
 
 
 //Loading Screen
 if (isLoading)
   Application .LoadLevel("Rotating Arch");
 }
 function Update () {
     if (Input.GetMouseButton(0)) {
         var ray: Ray = Camera.main.ScreenPointToRay(Input.mousePosition);
         var hit: RaycastHit;
         
         if (Physics.Raycast(ray, hit)) {
             if (hit.transform == target1) {
                 print("Hit target 1");
                 isLoading = true;
             
             } else if (hit.transform == target2) {
                 print("Hit target 2");
             }
         } else {
             print("Hit nothing");
         }
     }
 }`

Anyway..

This works fine for those buildings that have single meshes. But sometimes when the model has multiple meshes...I choose the one that covers all parts of the model(that's where I put my collider) then test if it will take a "hit".

Apparently...it does not work.

NOTE: in the code sample there are 2 targets only. Because I test the buildings 1 by 1 first to know if I put the colliders in the right mesh. But in the long run...once I have all colliders in the right place I will have multiple targets.

The goal is to make each building "clickable" so that when it is "hit" it will go to a scene where it's details are shown.

The problem is that Multiple Meshed models seem to not work for this code. :( I need to fix this asap for this is part of my thesis XD

Did I do something wrong? Is there any other alternative for this kind of thing?

ANOTHER NOTE: I attach the above script to an FPS Controller. This is part of a "Free Roam" function of my thesis. More of a digital tour of a place :)