Best way to customize ofxUI and other GUI ?

Hi there,
I’d like to extend/customize ofxUI especially.
This would be more customization than extension, really.

What would be your way for that ?
To duplicate the ofxUI folder and work on files ? or To create button2.h, button3.h all refering to the ofxUIButton.h class definition and to extend this class by replacing some draw function etc ??

any help would be appreciated.

first of all, you should fork the repository on github, and work on your copy. that way, any changes you make can easily be incorporated into ofxUI if there’s need/want for that.
then, you should probably ask the author (reza), cause he knows his addon best. the big ofxUI thread is probably the best place.