I'm trying to figure out the laws of your state. I'm in Calif. and work for an attorney service.
What they originally served you was a complaint or summons and complaint. In our state you get 30 days to answer. I believe you said you answered the complaint, but didn't serve the opposing attorneys with your answer. If it's still under the 30 day period, or whatever your state requires, make a copy of your answer and also fill out a Proof of Service form and serve the law firm that is suing you. That will make everything legit.
They then will probably send you Form Interogetories which asks you every question in the book. If you don't fill out these forms, they will file for a default and try to throw out your answer.
By the way, if your state is like Calif., you don't have to pay to have the law firm served. Anyone 18 years of age or older can serve them for you, like a friend or relative.
I haven't read the entire thread, but I will now and see if I can help you out a little more.
I didn't realize this thread was so old. But this might help someone else who winds up in the same boat.