I installed Brian's Threaded Comments and now my comments are gone. Additionally, the box where comments can be written is not showing up either. Please feel free to check out my site to see this issue: http://www.lauralohr.com
I tried to deactivate and to completely delete (and undo, replacing the comments.php file with the one before the install). The comments are still gone.
Any suggestions and help are greatly appreciated. My comments are disabled indefinitely until I resolve this issue.