Secondly how to handle what to show in public activity?

Thanks.

I think you can do this by:

1- Appearance > Widgets > Add a Text Widget and use the shortcode: [userpro template=activity], then move the widget to the sidebar you want to display the activity feed.

2- You can use these options:

Options are used to customize the shortcode and can be assigned as a pair option=value in your shortcode like this.

[userpro template=activity option=value]

activity_all – If this is turned on, activity will be public (All users activity) – If this is turned off only activity of “followed users” will show. Default: 0
activity_per_page – Number of activities to display per each load. Default: 10
activity_side – Enable/disable instant ajax refresh of activity with ajax loader. Default: refresh (enabled)
activity_user – A comma seperated list of users (as IDs) to include in activity feed. Example: to limit activity feed to specific users by IDs only. Default is empty (show all users)
activity_heading – The title of activity feed widget. Default: Recent Activity

It works.