Sam, I will not be using advancedvoip if I was you.
I bought and paid for that software diecttly from the people that claim that they wrote it.
The system did not work, they have basic troubles that they could not fix, the customer service is a joke and they a bunc of very unprofessional people.
Unless you like to expend countless hours on IM, only to repeat the explanation of your trubles over and over to people that do not care, stay away from those guys.
Wilson Boyrie.