Thanks for the dump. It's a strange ROM type so it's maybe bad? I doubt it's encrypted and there's normally some kind of plain text readable either directly or with a bit-swap with the manufacturer's name or a date or version number.
Since there's none of that it could be bad.
To figure it out will require tracing the PCB.
Regardless, even if it's good, the NUON dump is incomplete.
There's also an Atmel AT49BV1614 smd flash ROM in the lower left corner of the PCB.
you'll need to dump it before we could add emulation or a basic skeleton driver to MAME.
or send it to someone who can dump it and guarantee it'll work afterwards (i.e. me ;-)