History tells me not to rule anything out but I am not aware of any issues w/ administrators. It is possible that an admin doesn't have 'view' permissions to a Private forum (which is by design). When developing the module, I spend most of my time as a user as an admin so it probably gets the most 'testing' that way. What I would do, to make sure things are ok (If it isn't a private forum you are speaking of) is to check the permissions (via Settings) on the module and click update just to make sure. If that still doesn't do it, let me know more specifically what the issue is.

Added the admin user, then removed the admin user, then it worked as expected. weird..