These options can be entered by the add-on owner in the already provided input fields while creating the add-on or these can be generated automatically by parsing the add-on files/templates.
In 2.x or even in 1.x, I would like see, everything on the one screen:
Home > Options >
Location 1 [CSS][Templates][Phrases][Classes][Files][+ Add Option] [Display Order] [Edit Group]
or Location 2
Related CSS templates/files: