Instantiate in Scene view not in play mode

Questions & Answers
1

How can I execute the following script whilst not in play mode (e.g. in scene view)? 

var ground : GameObject;
var numberOfBuildings : int = 20;
var inititalBuildingNumber : int =20;
var numberOfRows : int = 5;
var building1 : GameObject;
var building2 : GameObject;
var building3 : GameObject;
var MyPosition = Vector3(10, 0, 10);
var buildingType = 4;
var zchange = 10;
var nothing : GameObject;
var rowchange = 0;
var rowchangeIncrease = 10;
function Start (){
inititalBuildingNumber = numberOfBuildings;
var newObj = Instantiate (ground, Vector3(0,-0.1,0), transform.rotation);
newObj.transform.localScale.z = numberOfBuildings*40;
newObj.transform.localScale.x = numberOfRows*100;
}
function Update () {
if (numberOfBuildings > 0) {     
buildingType = Random.Range (1,5);   
print (buildingType);  
switch (buildingType) { 
case (1) :   
Instantiate (building1, MyPosition, transform.rotation);
MyPosition += Vector3 (0,0,zchange);
numberOfBuildings--;
break;
case (2) : 
Instantiate (building2, MyPosition, transform.rotation);
MyPosition += Vector3 (0,0,zchange + 3); 
numberOfBuildings--;
break; 
case (3) : 
Instantiate (building3, MyPosition, transform.rotation);
MyPosition += Vector3 (0,0,zchange+3);
numberOfBuildings--; 
break;
case (4) : 
Instantiate (nothing, MyPosition, transform.rotation);
MyPosition += Vector3 (0,0,zchange);
numberOfBuildings--; 
break;
} 
}
else { 
if (numberOfRows > 0){
print ("next"); 
MyPosition += Vector3 (rowchangeIncrease,0,-(zchange*inititalBuildingNumber));
numberOfBuildings += inititalBuildingNumber;
rowchange += rowchangeIncrease;
numberOfRows--;
} 
}
}
2

http://unity3d.com/support/documentation/ScriptReference/ExecuteInEditMode.html

I'm not quite sure, but my experience says that Start runs a) when you create the object and b) when you (re)import the script (save it), or c) restarting Unity. If it's acting flaky, you may want to fold the Start script into the Update, something like:

var started = false;

function Update()
{
  if (!started)
   Start();
  started = true;
.. the rest of it..