
About the dialects, I've been a few times in Euskal Herria, and as I've seen, even being the dialects very different among themselves, they are perfectly understable each other, between different native basque speakers. By the other hand, some dialects yet become too hard for non-natives and batua students. The biggest differences among dialects are between Biscaian(in Spain, the most western one) and Zuberera(in France, the most eastern one).
Anyway, since I'm not basque myself, I'm not the most indicated for discussing about these matters

Check this site: http://www.landarbaso.miarroba.com you'll find a lot of information about dialectal basque. In the "dialectos comparados" page there is the auxiliary verb put in all the dialects.
Agur!