Pls explain the construction of default quark vs. offsprings

I'm not sure if I'm missing something or can't find the correct answer: I can't understand the logic behind the Quark structure - so we have the default Quark and then you added Quark/Restaurant and Quark/Ecommerce...
So I have installed the quickstart Quark/Restaurant and it's prompting me to update to version 1.2.0 - Where do I find that version? is this the Default Quark version, or is there a specific Restaurant (or, following that thought, an ecommerce) template package?

When I compare the package (= find differences via BBEdit) of gk_quark_J!3 (unzipped package) with a qk_quark template from gk_quark_restaurant_quickstart_J!3.zip (downloaded today, June 1), then I see bunch of them...

I'll really appreciate if someone could explain in plain english (or polish for that matter) the process of how one should update the Quark and it's offsprings (e-com, restaurant) - thanks,
AZ

This is a really good question. I need to ask it to our devteam.

Ok, There are 3 different quickstarts, but one theme. The theme contains all necessary files for all 3 "looks" that quark can have. The differences you see are probably because you had first or second version while now there is something more in template itself.