I am running 3.5 Release Candidate of WP. This plugin seems to work fine except that when I activate the bbPress plugin, I should see extra roles such as "Participant" but I don't. I have users with the role Participant, so the role is recognized by WP/bbPress, but the Multisite User Management doesn't seem to know it exists.
I tried deactivating all plugins and then re-Activating only what was required: the bbPress plugin and this one. Still no luck.