We have updated our Sample So you have no need to specify Game object in our current Sample,It takes the default name (Main Camera) as a Push Title. if You want to change this you can change accordingly.So we have specify it in our previous version.
	You can check Pushsample.cs file.
	public void RegisterForPush(){
	         object[] googleProjectNo = new object[]{Constants.GoogleProjectNo};
	        object[] unityParam = new object[]{Constants.CallBackMethod,this.gameObject.name ,UnityRegistrationMethod};
	          using (var actClass = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) {
	                playerActivityContext = actClass.GetStatic<AndroidJavaObject>("currentActivity");
	             using (var pluginClass = new   AndroidJavaClass("com.shephertz.app42.android.pushservice.App42PushService")) {
	                if (pluginClass != null) {
	                    testobj = pluginClass.CallStatic<AndroidJavaObject>("instance",playerActivityContext);
	                    testobj.Call("setProjectNo",googleProjectNo);
	                    testobj.Call("registerForNotification",unityParam);
	                }
	                }
	            }
	    }