SD:
I'm assuming that the talk of putty (and rm -rf /) means that you have discovered that there's a linux / unix OS powering the NAS and that you are contemplating firing up a blowtorch to make "adjustments"?
Yup

It's running BusyBox on Linux.
Having established what SSH is (something else learned as a result of the problem encountered) and how any command line hacking automatically invalidates the warranty I was amazed to then find "Enable SSH" as an option in the Admin console! Sure enough, duly enabled and using aforementioned Putty I connected first time using root/welc0me.
At this stage I simply want to do two things:
1) Change the root password!
2) Kill the MioNet service by removing the start command. A quick Google has revealed some possibilities on how to do this but I don't want to end up with a brick instead of a NAS so I'll "measure twice (or three times or four) and cut once".
mixture:
I couldn't agree more!