The current configuration is stored automatically whenever a change is made. The data is stored on the HOME server. If the server restarts, then the configuration is re-instated at the end of the reboot.
If a networked device restarts, or is disconnected, then any streaming connections to and from the device are lost. However, the connections are still prepared. This means that as soon as the device comes back online, its streaming connections are re-established.
If you wish to make a backup of a particular point in the setup, then you can save the complete configuration in a snapshot. For more information on how to do this, see HOME - Snapshots.