I was looking through joomfish to see if i could translate the contents of the custom registration form and i was unable  to do it. I was wondering if there is a way to edit these fields so when a user changes to SPANISH then the registration form is in Spanish as well. Maybe modifying a php files?

Hello Rodrigo,

You need create several language files as it described in JUser FAQ section.
For database translations use JoomFish xml file that is placed into component download section.

Regards
Dmitry Lapshukov