Drupal 7: How may I customize the user profile? And how do I add to it profile2 fields?
I don´t know if I should respond to my own question, because after two days not only I didn´t received any answer (which isn´t bad in itself, because nobody "has" to answer), but I´ve received a minus one point, without ANY explanation at all, wich I think is rude.

Anyway, as I´ve found by myself the problem, and other people maybe has the same issue, and as a good citizen, I shall say that the it was the "Display Suite" module. 

That module, wich is installed in more than 45.400 sites, was the only reason my Drupal installation didn´t recognized the user-profile.tpl.php file.

I´m going to read more carefully DS readme, tutorials ans screencasts out there because it´s a more complex module than I thought it was. But people should know that it does that (at least right out of the box, in a D7 installation with some core profile fields, Profile2 installed, and without any tweaks in the default configuration).

Cheers.

Rosamunda