Yes, Rabet, I actually went to my recycling bin to dig out the appropriate paper! I, too, was confused at the time. I got the same structure as you did re the anagram of 'has' and the idea that the Shannon was a long distance "runner". Thus I had SHA-N-N, given the crossing down-clues, which meant 'Shannon' was certainly what was required.
The only reason for the NNON that I could subsequently find was that the words 'lungs' and 'cannon' appear together in Roget's Thesaurus to signify 'loudness'. I suppose 'nnon' could just about half-reasonably be described as an 'assortment' from 'cannon, but that seemed far too thin a connection to me. I tried a Google search using lungs+nnon, but most hits seemed to be mis-spellings, such as 'nnon-Hodgkins lymphoma'.
In conclusion, I am as puzzled as you are!