No, this code merely allows other user roles registered to WordPress to be able to use the Thread comments feature. Out of the box XFtoWP enables it for the Admin and Editor roles.In Thread comments settings you can assign the create/connect thread ability to the Editor and Author roles. Use this filter to add your own custom roles to the settings page…xftowp.com
Does this code work when an author is publishing a post, it will also create a thread in the author's forum username by adding the roles into the piece of code you have on that link?
Also, where do you place that piece of code?