How to get beyond nickname screen?

Not even sure this app works at all?. Upon starting app, a form asking for nickname and password which are effectively not the same as username and password of the user profile is the critical barrier! I contacted support twice to no avail. Didnt ever reply to me at all. Hope I am missing something and the app actually works?

ALIHK about Talk the Talk - Mobile VoIP, v1.0.0