Well ... I booted into flash, performed update (n810 would
not update from sd). Ran the new initfs_flash to reinstall
bootloader. All seemed to go well.

But now I can boot into flash normally, and I have the
multiboot menu, but if I try to boot to SD, the blue bar
gets half way and the device reboots ...

I guess I must re-clone the system to SD ??

What a PIA