Cultural background subtleties vs. a language discussion?

While reading the English-Italian discussion of Eric and Marco, I had the impression that it is the top of a very, very huge iceberg. Just a few examples:
  a.. Indeed, most of the content in a book can be translated more or less correctly. However, this holds true to a much greater extent for a technical manual than for a Shakespeare or Petrarca sonet. 
  b.. Or a simpler point: How do you translate into Italian "It rains cats and dogs"? In my mother tongue, Bulgarian, the idiom says "it rains as if pooring out of a tin" which has quite nothing in common, lexically or gramatically, with the English one. 
I favour the opinion that in languages, there is a large portion of some sort of "non-verbal communication" basing on common cultural patterns. I had an experience of this phenomenon myself when participating in an international essay contest limited to the UNO languages + German. From their interviews I had the impression the German jury that reviewed my essay was unconsciously looking for their own cultural patterns and, therefore, unconsciously rejected most of the pieces that did not fit into them - except of the most picturesque ones. Further, being not so familiar with French culture, I had myself great difficulties in comprehending the ideas in the French essays I come to read afterwards.

I think successful i18n should address this kind of issues, too, beside technical matters. Maybe in terms of finding out and cultivating transcultural communication styles and habits?

My questions:
  a.. Does anybody know about research done on cultural patterns, or context, and what is the correct term for it? 
  b.. What kind of approaches have been tried out - I know of culturology, linguistics, AI, cognitive science; but with so complex a topic, there certainly must be much more.
  c.. Does it relate to the concept of cultural networks, if someone can define this one?
  d.. Any experience as to which nations have more rigid cultural frameworks imposed on their thinking patterns, maybe depending on the size of the nationality? Does this relate to the wilingness/ability to learn foreign languages?
  e.. If this is the wrong mailing list, please give me some hints where to go

Thank you for helping,
Kremena