So I've setup the WHMCS Module for Centova and created the server, when I go to WHMCS to list Servers I can click the link to login to Centova admin portal and that works just fine, however when it goes to create an account I get the following error:

Module Create Failed - Service ID: 2 - Error: Socket error accessing https://s1.domain.com:2199/api.php: fopen(https://s1.domain.com:2199/api.php): failed to open stream: Connection refused

When I go to the API url I just get an XML error which I've never been to the API URL so I don't know if that's what I should get anyways?

So I'm not sure how to troubleshoot

This XML file does not appear to have any style information associated with it. The document tree is shown below.
<centovacast version="3.2.12" host="s1.domain.com:2199">
<response type="error">
<message>XML root tag not found.</message>
</response>
</centovacast>