I don't believe segmented hashes are so important for sharing incomplete files.

I already played around a little with the source code to make LW share incomplete files (was too lazy to complete it, though), and implementing it would not be hard compared to the amount of work it takes to implement HUGE properly.

I think it could easily be done after LimeWire supports HUGE without the need for segmented Hashes:

A & B are LimeWire nodes

A could search for a file by hash, B would answer, that it has got the file, although having only parts of it. A would request the parts of the file it wants (could be multiple parts when using HTTP 1.1), B would either send subsections of that parts (A could easily adjust to the ranges sent by B) or respond with an HTTP Error "416 Requested Range Not Satisfiable".

There is no point where you need hashes for this process.