In that case i'm unsure what the implication is. It seems from the info you gave previously that Updater consistently identifies the device alternately as O600 and O750t, the former when flashed with 6x0 fw and the latter after a failed boot. Perhaps because the device has lost it's HWID (showing '0') is will not read the ID data in the GCD file before initiating the file to try flashing the device. If there is a corrupt GCD file on-board the flash will fail and soft-brick the device. Usually an inappropriate GCD is not flashed because the device first checks the file's HWID against the device's own and if they don't match nothing further is done.

All i can suggest is to try again to flash Cure fw made from O6x0 fw. Your only chance may be to re-enable Mass Storage Mode so you can remove any GCD from the internal memory. Re-make the Cure from scratch and be persistent if the flash fails, try over and over, reloading the cure RGN into Updater and shutting down the device between attempts.