You're welcome to hijack away. I'm sorry that you too have suffered a similar problem. It's astonishing that by rigidly following installation instructions, you brick the box and that there seems to be no recovery. How can any company make kit that requires firmware updates, without some form of recovery mode? Either they are almost criminally incompetent, or there is some way that no-one seems to know.
I've not binned my cs410 yet, but it now sits in its box as a sad reminder to not buy cheap IP telephony kit again.
If you get any better luck than me, please share it here.
Regards
Richard