> I managed to get past the first form-based login page 
using 
> catchurl. But now, every link that httrack is trying to 
> follow returns the same login form again. Any ideas 
what's 
> going on?
Yes - the capture URL did not work. Either because the 
cookie expired, or for some other reason.. it strongly 
depends on the remote server authentication system, in fact.
Ensure that all necessary filters have been defined.

You can also turn on the extended debug log 
(options/experts), to figure out what happened looking at 
requests/server responses.