Warnings

• Do not use the Virtuozzo Power Panel to enable Firewall. The Default (Normal Firewall Rules) turns on a set of rules which may lock you out of Cpanel. If you enable the firewall (which is really already enabled through iptables), then choose Default Policy Accept.
  
• Do not use the Virtuozzo Power Panel to edit any files on the server, especially httpd.conf. This editor will destroy your files.

• Do not change your VPS hostname to a subdomain name in use by any account on your VPS. Things will break. Instead, choose a distinct hostname, such as vps.example.com (the default) or some other random hostname.