Thanks for the reply. Everything's working now. I just didn't realize that there were a separate set of K2 template files in the Gamebox template folder when I got started. Basically, after I made the original changes to the default K2 template files, half my site was displaying the username and half was still displaying real names and I didn't know why.
I like the K2 component, but it's got a a lot quirks that I needed to learn as I was building my new site. The component really should have a global parameter so that site admins can choose between displaying real names and usernames.
On a side note, I don't suppose that you're considering updating Gamebox for J1.6 at all?