Zoho Mail Add-on User not showing

My List of Zoho Mail Add-on Users under SETUP > USERS & PERMISSIONS does not show one of the users that I have recently added. The user has been activated in the Subscription Manager as a Zoho Mail Add-on User. I have also checked licencing. Don't think that this is the problem.

Also:

When I login to CRM as the user in question and try and configure ("CONFIGURE NOW" Button) the Zoho Mail Add-on I get the following error "Unable to process your request"
When I goto Apps & Add-ons > Google Apps > Zoho CRM for Google Apps and attempt to login to Google Mail account, it does not work.

Please help.