Update on this.
I now have this Firmware update from Yamaha, to update from V.1.0 to V 1.4 BY USING FLOPPY DISCS which is the original way of doing it.
This is the original update zip file NOT the newer USB updater which is for Windows 10.
I'll save it somewhere safe on my computer, so if anyone else should need it, just let me know.
I have already unzipped the files, so all that's needed is to copy them to 14 Floppies ready for the upgrade.
Keith