1) Is it possible to use Unity IP Fax in a VM environment or you need licenses of UM?
2) The idea of this tool is to convert the Unity in a fax server?
I think that you need licenses of UM to get fax capabilities.
In this situation Unity receives faxes as emails, so you have a gateway to a fax server. I have made tests with Rightfax and Exchange and you need a conector in Exchange that it sends the faxes to Unity as emails. Then you can send faxes from Outlook to a fax number using the fax server through the conector set up in Unity.
Hope this helps,