You can ensure your world is safe from griefers by having a backup available. Your server will backup daily automatically but if you wish to create a manual backup, do the following:

1. Go to Clanforge -> Servers -> Live Control -> World Options

2. Click 'Backup world'

To restore a previous backup:

1. Go to Clanforge -> Servers -> Live Control -> World Options

2. Choose relevant backup from the drop down menu

3. Click 'Restore World'