Probably it's me being dumb :)

yet I cannot understand how this module should work :(

My need is to produce book pages that can have an embedded audio file (same text read as a Pod cast, we deal with languages that have a low alphabetization rate). So this looks like exactly what I need. Book page is "parent", audio is "child" in a 1-1 relation. So okay, I enabled the module and so I stated in the administration interface.

Only... where am I expected to load this audio node from?? And how will I couple it with its parent?

I have to add that I also use "Node Relativity" to build Directed Graph relations among book pages. Hope this won't make things too hard, anyway, Relativity is for sysop use only, a normal user should see Node Family and nothing more than that.