nand-sata-install simply works. It transfers the rootfs (your OS partition) to connected USB/SATA storage and after the following reboot only the bootloader remains on SD card but the whole OS lives on USB/SATA storage. But this doesn't make sense if the storage on a HC1 or HC2 is a HDD and the disk should spin down since with the rootfs on this HDD it will either constantly be woken up or you need to configure the HDD to never spin down.
Thank you. I'll take a look on this. Also the spin down concept is new for me.. This is my first NAS I build.. But I;m already reading a few things about it.