Three Problems Solved, but a New One Appears

Thanks to Christopher Roberts, who is a regular commenter, for helping me find the answer to the question, "Has Anybody Here Seen My Old Friend Threaded Comments?"

When I upgraded WordPress, Brian's Threaded Comments plugin quit working, and I couldn't get the threaded comments in WordPress to work. Gravatars have never showed up in comments since I started using this theme, although the gravatars show up in the dashboard. And new commenters told me they didn't get any message their comment...