Any Service mode experts?

[Seekerr]

Hi all

I recently purchased an MZ-N707 secondhand....anyhows, all was fine up till the other day, when it failed on starting with "NV Error"....anyhows, I've got a copy of the service manual, but I can't seem to navigate service mode well enough to follow the procedure to reset the NV values and then reset the variables to their correct state. Is there anybody out there familiar with repairing minidisc units that can give me a hand at trying this fairly last ditch effort to save my bricked MZ-N707?

Thanks for any help (or advice to just buy a MZ-NH600 for cheap instead....at 1/5 of the price of an RH1, it's really my only option for a new minidisc unit, even if I'd hafta get a pre-amp to use it with most mics)