VPN question

We just set up our VPN, and have it working just fine right now. One question, we are using RealVPN as our client/server, and have no problems with the connection or viewing, but I need to find out how to copy files across. I was under the impression that once the tunnel was connected, it was just a matter of cut/paste.
Not sure if I am doing something wrong, or I need an additional app. TIA.