playgame service plugin integration

Hi guys,

I am trying to integrate Leaderboard and achievement system through "google playgame service plugin". I have follow all the steps mentioned in the documentation, unfortunately i am not able to signin into google...

This is what i did so far... please do let me know what i am missing or doing wrong.

1. Created fresh project using unity 5.1.2f

2. created new keystore, bundle ID and package name.

3. Build apk and uploaded on android devloper account as new app.

4. created new service , setup few achievements and one leaderboard (test ready)

5. downloaded latest "play game services plugin " from here.

6. Imported plugin into unity and did android setup.

7. Created one simple scene with few gui buttons to Sign in, post score, show leaderboard ui, show specific leaderboard ui, and sign out button

8. saved and build...

while testing i am not able to sign in into google account...

I have few more questions. I am on windows 8.1 64bit 1. Which android and JDK version should i use... 64 or 86x 2. Java home and path variable should point to both versions or any one of them.

Actually i have tried both things but no luck.. please some one help me... i am attaching code below may be something is missing from there...

I am really out of ideas and need your help. Thank you

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 using GooglePlayGames;
 using GooglePlayGames.BasicApi;
 using UnityEngine.SocialPlatforms;
 
 
 public class lbManager : MonoBehaviour {
 
     public Text debugText;
 
     // Use this for initialization
     void Start () 
     {
         PlayGamesPlatform.Activate();
     }
     
     // Update is called once per frame
     void Update () 
     {
     
     }
 
     public void signIn()
     {
         Social.localUser.Authenticate((bool success) => {
             if(success)
             {
                 debugText.text = "signin successfull!";
             }
             else
             {
                 debugText.text = "signin failed!";
             }
         });
     }
     
     public void postScore()
     {
         Social.ReportScore(12345, "Cfji293fjsie_QA", (bool success) => {
             if(success)
             {
                 debugText.text = "score posted!";
             }
             else
             {
                 debugText.text = "score posting failed!";
             }
         });
     }
     
     public void showLB()
     {
         Social.ShowLeaderboardUI();
     }
 
     public void SLB()
     {
         PlayGamesPlatform.Instance.ShowLeaderboardUI("Cfji293fjsie_QA");
     }
 
     public void signOut()
     {
         PlayGamesPlatform.Instance.SignOut();
     }
 }