After a bit of work, the challenge systems have been updated and the registration has been reactivated. Hopefully, these will keep out most of the automated spambot registrations. Going beyond the registration system, new users are required to make at least one post in the New User forum before posting rights are granted for the rest of the forum. I apologize for any inconvenience. You can just make a short “High I’m xyz” post.
After not paying attention to the site for a few days it seems that the spam bots have found a way through all of the spam security features for user registration.
To drudge through the mess manually pruning each forum would have taken at least a week. Luckily, there were only a handful of valid posts on the forums. So I simply wiped the forums completely and purged the user banks of all but one I was sure was not a bot. If your user account did get wiped, please let me know or if you have trouble re-registering.
From now on, all user registrations handled by the forums require my approval before they can be activated. Until I can secure the user registration, this is the only way to 100% sure cut out erroneous user registrations.