How To Lock/Unlock Map as this picture

How To Lock/Unlock Map as this picture !

I want Players need to collect items to fully customize the system to unlock the screen.

How do Tutorial with javascript

thank you

you need to store the player stars, and the only check with a if statement. If it result true then chapter is unlocked, else is locked, and then you will use this as boolean in you ongui function and display this message.
If you are a newbie then:

var playerStars : int;
var chapterUnlocked : boolean;
function Start () {
  chapterUnlocked = (playerStars > 9);
}
function OnGUI () {
  if (chapterUnlocked) {
    //GUI here!
  }
}

Got it? if you need you any help send me a message!