I have the same issue with LiveSupport and DNN 4.7. The URL is correct, but I have no users in any of the DB (perhaps it is using the DNN DB). I can configure the DNN module, but I'm unable to create operators and therefore I'm unable to login with the Client. Is there a way to manually create an operator, so I can test whether I'll be able to login with the client at all. For the record - the standalone LiveSupport works, so we know how to configure it and create operators, use the URL etc
May be your issue is the same - you do not have defined operators