I'm signed in as a regular user. I tried to click on the "Post Reply" button at the bottom-right of my Administrator's reply to your post. But nothing happened. So I'm using the "Quick Post" text input field that shows below my original reply. I'm hoping this posts as a reply in turn.
The "Post Reply" button only seems to not work on this category's forums. It seems to work on all the other categories' forums. Maybe I set that option somehow when I created the Test Area? Oh well, the "Quick Post" works fine to reply to a posting.