How to implement Amazon Gamecircle

I downloaded the gamecircle api of amazon from asset store and I am following this tutorial from amazon https://developer.amazon.com/appsandservices/apis/engage/gamecircle/docs/unity-setup

I am stuck at section 1 step 3. The codes are in c# ( I use JS) and I really can’t understand what to do next. Any help is appreciated. Thanks…

I used this for and older version of the plugin but it should be almost the same.

private var usesLeaderboards : boolean = true;
private var usesAchievements : boolean = true;
private var usesWhispersync : boolean = false;
    
    
function Start () {

		 AGSClient.Init (usesLeaderboards, usesAchievements, usesWhispersync);

		//Will return true if service is ready
		var isServiceReady : boolean  = AGSClient.IsServiceReady();

        //To show Leaderboards use this: 
        AGSLeaderboardsClient.ShowLeaderboardsOverlay();

        //To show achievements: 
        AGSAchievementsClient.ShowAchievementsOverlay();

        //To submit scores, replace with your variables:
        AGSLeaderboardsClient.SubmitScore("YourLeaderboard",YourVariableToSubmit);

        //To unlock achievements:
        AGSAchievementsClient.UpdateAchievementProgress("YourAchievement",100); 
	}


function OnEnabled(){

		AGSClient.ServiceReadyEvent += serviceReadyHandler;
   	 AGSClient.ServiceNotReadyEvent += serviceNotReadyHandler;
	}
	
function OnDisabled(){

		AGSClient.ServiceReadyEvent -= serviceReadyHandler;
   	 AGSClient.ServiceNotReadyEvent -= serviceNotReadyHandler;
	}


function serviceNotReadyHandler (error : String){

	    Debug.Log("Service is not ready");
	}   
   
function serviceReadyHandler (){

	    Debug.Log("Service is ready");
	}

Hello, I wrote a tutorial of how to implement GameCircle in Unity3d using Social API… I think is more easier that way… you can take a look in my post