reload css file after compile

Hi

I have 2 question about sass in phpstorm

1) reload file after external change

I use external processor to compile sass/*.scss to css/*.css . When I open the two files ( index.scss and index.Css)  in a windows tab to see the change in real time . When code change in scss file then the second tab that contain the css file don't update even i know that the content change. I have to select ( get the focus) on other windows OS application and then reclick  in phpstorm application ( don't have to give the focus on the css file) to see the real content of the css file .

Is it the default behaviour of phphstorm ? !!!!  Is there a way t oconfigure phpstorm for that all files manage inside a project folder and open  in the tab and content viewable that phpstrom update the rendering of the file content when change occur inside this file  ( by alert us of change occur or without ask if the content of the file should be update )  ?

 I want to use phpstrom for edit scss file without use phpstrom  functionnalities for preprocess the scss file !

2) completion for ruby library or external sass librairy ( susy)

I test to call thefunction darken(a,b) and completion work inside phpstorm for  scss content file . So i install susy in global ruby directory  but i can't call for exemple the function/method container() .

Is there a way to use susy without install susy sass files/directories   inside my project folder directory ?

I can see when write @import "susy ; in the begining of the file a popup info " canno't resolve import into ...." 

If phpstorm do completion for sass by default is there a way to configure phpstorm to support external sass library like susy to have completion .....after install libraries ( susy ) in ruby directory like sass ?

Thank's