I've snail-mailed them a letter based on what Moritz had posted. They replied with a standardized letter without even commenting on my statements. It's basically saying "Last chance to pay or we'll go to court."

So I'm a little unsure whether or not it's now time to actually consult a lawyer or wait until FOX makes it's next move.

I believe what some others were saying is to simply ignore any initial complaints that come in which appear to be automated or are in some way not sufficiently personalized, lacking in real data, or stamped by a court. Just because someone complains from getting emailspam or can scrape peers off a tracker could just be a courtesy or idle probe. If such first notices bother you, sure, have an initial consult with a lawyer for potential future engagement if needed. But now that you have snailmailed them, it is raised on different level. One for which some would surely say a five minute chat with a prospective lawyer is wise. Also, if other people on the list get such first notices and don't know what to do with them, redacting any identifying material and posting the remaining full text [from an anonymous account if prudent to further avoid confirmation] would let others get a sense of what is out there and offer any experience. Just saying 'I got a mail about filesharing from my node and I mailed them back' doesn't help the poster or others. Then again, we're not lawyers, consult a real one as needed.