Once built there is NO maintenance to the CDs. If you need to change the private key password for the the individual user, burn them a new CD. If they lose a CD, give them a fresh burn. If the CD gets destroyed, give them a new copy.
The openVPN server requires little maintenance. It is recommended that you periodically check the openVPN logs on the server to determine the likelihood of nefarious activity and act accordingly. Usage-tracking is beyond the scope of this document.