Great stuff, thanks.
I have just commented the 3 USB lines and will reboot once the raid sync will be done.
It's very suspicious anyway that sda1 was the main SD partition where OMV was installed, sda2 was the extended partition containing sda5 which was instead the swap partition.
Just to confirm, if I add any USB device, these will be recongnized/mounted via the "File System" tab and would perhaps be listed as sdh/sdj/sdk, correct?
Thanks,
Tommy