What is the meaning of [no-xauth, no-config-mode]?
Disable VPN Software connection if run [no-xauth, no-config-mode]?
no-xauth is used the extended authentication, that is to have the user prompted for a user name and password before connecting
no-config-mode is used to disable pushing data to the user connecting through the VPN client like the ip address, the DNS server, WINS server ....
both of the above are mandatory to exist when connecting using a software VPN client.
I hope that the above answers your questions.