I did a new install off OMV on the T610, which was a pain, because Grub wouldn't install right..... Which I was able to manage manually.
After that I started configuring OMV with "guest allowed" when sharing folders. Makes things easier, I guess, in the beginning.
Data copying is from ntfs data disk is almost done. Than I will try USBbackup again... to copy all my data to the NAS.
So far so good.
Edit: What I did wrong, without knowing, the first time I tried USBbackup, is trying to choose a folder with the + button, instead of the v ( Arrow down ) button. Not knowing they have different results.. As a total newby I thought they had the same functionality.