I received a phone call yesterday from Yamaha service rep, in response to an email I send questioning the Flash Rom/Eprom situation. The rep did indeed affirm that the os is not upgradeable in flash rom. He apologized, but referred to the disclaimer about "all specs subject to change".
He also said that he had heard nothing yet from Japan about the harmonizer bug, but that my "case" was still pending.
It's been "pending" for two months now.
DonM