I found the problem. It turns out that all of my Role definitions were full of errors. I ported my data from Moodle 1.9.9 and assumed that the Roles would be the same. But in Moodle 2.0, the Roles were very different.
I opened the Define Roles utility and reset all of the roles to the Default settings. This fixed a lot of things that I thought were bugs.
Clarence