Same problem.
Last lines in logs:

l[4744] UcLoginRenderer.onJavascriptConsoleMessage "Callback for fb found:function (i){b.processLogin(i,c)}" from:https://panzar.ru/_assets.axd/site-common-js/-110750837/(135) [2016:05:06 21:29:41.356 PnzUcHtmlRendererEvents.cpp(304)]
l[4744] UcLoginRenderer.onJavascriptConsoleMessage "{"authData":"https://www.facebook.com/connect/login_success.html#access_token=EAAGs75SN1yoBAP0WWGA3evdl8lnJOQvoOuTZB1dtzdQDcNYdu0kV73ApWbZA8aZAbeUO4fqREzYZBRFmx7VqyJol8iR066KdlKPy1UMbpRdxLKurMzXrKclZCP3yZCy92ejJVZBjS94vUS8OHi5KXNRZAnHLen1Eo6sZD&expires_in=5179168","callbackKey":0.31310719810426235,"cancelUrl":"https://www.facebook.com","hidden":0,"logOutUrl":"https://www.facebook.com/logout.php?next=http://panzarsite.ru&access_token=","script":"var e = document.getElementById('u_0_2'); if(e && e.parentNode) { e.parentNode.style.display = 'none'; } e = document.getElementById('reg_btn_link'); if(e){ e.setAttribute('target', '_blank'); }","successUrl":"https://www.facebook.com/connect/login_success.html","title":"Panzar","type":"fb","url":"https://www.facebook.com/dialog/oauth?client_id=471619966195498&redirect_uri=https%3a%2f%2fwww.facebook.com%2fconnect%2flogin_success.html&response_type=token&display=popup"}" from:https://panzar.ru/_assets.axd/site-common-js/-110750837/(135) [2016:05:06 21:29:41.356 PnzUcHtmlRendererEvents.cpp(304)]
l[4744] UcLoginRenderer.onJavascriptConsoleMessage "Login fb failed. No session obtained. Session response: {"authResponse":null,"status":"unknown"}" from:https://panzar.ru/_assets.axd/site-common-js/-110750837/(135) [2016:05:06 21:29:41.356 PnzUcHtmlRendererEvents.cpp(304)]

Hi,

1) go to website www.panzar.com and login with your facebook.
2) Go to profile and add a email authentication
3) Log off from website from your Facebook
4) Log in with your new attached email
5) if email logon works start launcher
6) Use email authentication
7) Game should start