So, which way do you want it to be shown?
It is our interface, and it works, as I see. But I don't know which way you have modified the template main_posts_cell.html so it inserts "Username" instead of actual username (login) on Forums. Like we do have here, on our board. It's probably your mistake! Take default files and compare them carefully... isn't this question out of our rules
It should work the way you described. You click on my name, it is inserted in the posts, and that way you're attracting my attention, replying to the post I've made (if you are replying more than to one post in the thread, you need to separate your opinions some way). You click on the community info link, and it displays some info about me.
But don't say "in phpBB I saw..." please.