I did find this FAQ:
“Instead, if a RAID controller is not used and you wish to create RAID software, then you must remember that the current releases of ZeroShell don’t offer this possibility because they don’t manage md (multiple devices).”
So, any plan for supporting software RAID? It has been available for Linux for years. I have been using mdadm successfully (both RAID5 and RAID1) since 2007.