With Linux, most administrators are very intimidated if they are not the Linux guru in their organization. With manual configuration, the users need to be familiar with the Linux shell. A great place to learn is Linuxsurvival.com this site gives several modules to learn the basic commands.
You should check your firewall settings if connections fail. Linux can block outbound traffic or inbound traffic. The administrator should check any rules to ensure data is allowed out on specific ports. The most common port for a Virtual Private Network is TCP port1723. Other ports such as ports 50 and 47 may be used if GRE and ESP are used. If ISAKMP is used, it may be necessary to open UDP port 500.
After a connection is made to the server, your workstations will obtain another internal private ip address from the server.
It is important to train users on how to use the VPN. Scripts can be added to map network drives to the server when using your VPN. This allows the user to have or share a folder on the server and ensures that whatever data is passed between the two is secure.
Remember VPNs play an important role in protecting your assets and critical data.