The VPNC interface right now allows you to set the group and user passwords, and save them if necessary.  However you cannot save just one of them.

If we want to automate steps as much as possible, we should mirror the underlying interactions done via the command line.  For example the group password rarely changes (set in the pcf file) but the user password changes each time I login.  Right now there is no way for me to have the nm-applet remember the group password, and prompt me for the user password when I try to connect.

When I run vpnc-connect from the command line, it reads the group password from the config file and prompts me for my user password.

The result here is that I essentially have to manually configure my VPN connect every time I want to use it, as my user password will have changed but my group password has not.

Perhaps simply de-coupling the save password feature so you can choose to save one or both of the group/user passwords?