hi there. pretty funny actually. Nobody has ever asked for delete category so it didn't exist!!! Just added it, please update to 2.1.1
in terms of adding audio or video to a page:
- add media items in the backend
- on a page in your CMS, add the ProMedia player component of choice
- make sure the component settings are set to accommodate the list you'd like - i.e. - filter by category of choice.