Hi,
As a new user, I sort of got in the position to "test" the Critters Web platform.
My story: due to my interests, I first subscribed to the Mainstream Workshop.
After finding it pretty much dead (last posting in August), I also registered to the flagship SF Workshop.
In order to keep things simple, I marked my membership in the SF workshop as "inactive".
As an unwanted result, also my SF access vanished.
In my opinion, you may have a problem with the normalization of your database (http://en.wikipedia.org/wiki/Database_normalization).
Even if the issue can't be fixed, please explain in the FAQ how the individual workshop accounts are linked to each other and how I or another user can manage them.
Thanks!