GoogleAnalyticsMPV3.cs : Line 126-128
WWW request = new WWW(newUrl);
while (!request.isDone) {
}

This while loop causes a lockup when run in the web player, per Unity documentation:
http://docs.unity3d.com/ScriptReference/WWW-isDone.html

This should be changed to make the WWW request inside a StartCoroutine and yield until finished:
WWW request = new WWW(newUrl);
yield return request;