It looks like the server is still having issues. I got a response from the admin and he said it's likely due to it being overloaded. Someone is probably hammering it with requests and so it's refusing to serve up stuff.
He can't log in yet to do something about it, but we'll update when we know more. For the time being it may be a little while before it's back up.
The good news is that this issue, though not common, will soon by a thing of the past. We had already been talking to the server admin about creating a tiled and cached 3D system that wouldn't be subject to the overloading issues.
The bonus is that it will be super fast for downloading, and TF will also cache the 3D data itself, killing the need for much of the downloading to begin with.
Once again, thanks for the patience. It shouldn't be too long.