There is no automated backup feature in Ksenos, but you can potentially work out something like it with external scripts.
Ksenos stores recordings in *.tt files, and uses separate database files (index.db*, timelookup*.db) for seeking. Archive the *.tt files from the capture folders to the network storage. If they ever need to be accessed, generate the required database file for the desired files using the DbTool.exe in Ksenos' installation folder.
For this you will need a folder for the backup and a folder called "a" inside it:
Place the *.tt files in the "a" folder and run the script:
DbTool.exe a=C:\ksenos_backup\a C:\ksenos_backup
This will create a database "index.db" inside the C:\ksenos_backup folder. This index then links to the "a" folder's *.tt files. Now you can move the "ksenos_backup" folder to another machine (or use it on the same machine) and open it from Ksenos "Open backup". You can also use the begin and end time parameters, if you wish.
For more information about DbTool and database generation, see (Re)Generating database using dbtool.