Hi,
I think it works the same as it does for MiVB if not please please let me know. I just want to help out and go from there but I assume the setup is kinda the same approach.
Just make sure you use the correct IP for the MSL.
Login into "IP"/server-manager
Go to "Remote Access" and make sure you are allowed to use secure shell access (trusted networks only)
Go to Networks and make sure the subnet you connect from is in the trusted list and routable.
Then open WinSCP and login as for example root or another admin user you created.
Go to Root and on the bottom there is a /vmail folder with all kinds of goodies to play with.
Enjoy,
Dutch