>>I think scepticism is in order here:

Thank you for your reply.  Scepticism is helpful, actually, because at least it gives a non-linguist some idea of what the problems are, and whether the question is worth addressing at all.  
 
 >>i) We are dealing with a very short name, therefore the chances of finding a match are enormously increased.

            True.

>>ii) We are dealing with a name starting with a very common letter - on average more than 7% of the names in all of the languages of the world that begin with a consonant will begin with N.

            OK.

>>iii) Criteria for determining a match are very loose.

            If you mean linguistic criteria, I accept your point.  Even I can see that just pointing at various names whose initial phoneme (if phoneme's the right term) or initial syllable happens to be the same, or similar, or vaguely similar, doesn't form the basis of a satisfactory argument, let alone proof.   As you imply, a series of such similarities could be explained merely as a series of coincidences.

>>iv) There is no explanation as to how the name could have spread, other than the Egyptian example.

            The Egyptian/Near Eastern diffusion of the word nwy is Bernal's suggestion.  I myself don't have explanations – I'm still in the process of seeking them!  The Noah of Near Eastern tradition is not only a flood hero, but an ancestor figure, too (hence the tradition about Ham, Shem and Japhet).   The Hottentot Noh and Hingnoh are ancestor figures – so I wondered whether "nwy" had at some remote point reached South Africa, in combination with the tradition about an ancestor figure.   The Chinese Nuwa or Nu Kwa was, as previously explained, a goddess connected with the flood; but there is also a tradition about using a vine to throw mud in all directions, each splatter of of mud then turning into a human being [McLeish 1996: 429.].  IOW, she was an ancestor figure, too.  (The other examples mentioned in my earlier post have too much potential for possible contamination to be cited by way of real evidence at the moment).

As you say, the linguistic evidence by itself is weak.  However, it's the combination of that evidence, in conjunction with the two traditions about a flood and/or an ancestor figure, that I find so curious.  Is it possible that the examples cited above could really have developed independently along parallel lines?

>> Sorry, but I don't think it's plausible without other evidence.