newbie doubts in sails js

[German Martinez solis]

hi  everybody, i'm newbie in this framework, i have some doubts and i hope somebody can give me a hand:

sorry for my bad english im from Mexico 

First: How can i save records with  associated models?, for example in cakephp i used something like that :

$this->User->saveAssociated($this->request->data)

and in the frontend  : 

$this ->Form ->hidden('StudentProfile.semester')

second: do i need load passport.js to do a login function or not?

third: if i wanna develop an SPA , how can i disable routing in sails.js to do it via angular.js 1.5.x? by the moment all that i do  for the rest backend  in my routes.js  is:

'POST /signup':'UsersController.signup'