Hi Hipoonios. Got to say that this whole sordid affair pretty much sums up what is bad with the world today. Luckily there's a lot of support here - both logistically and morally - and it's evident that common sense seems to be the weapon of choice.
I'm not a lawyer, nor have I ever been sued. However, I've seen enough consumer shows on TV to know that you must NEVER pay a penny without getting some legal advice. So, print out everything you have and see a solicitor (or lawyer, or legal councillor...). In the UK there's a load of them offer a free initial consultation, hopefully there's a similar approach in your neck of the woods. Even if this is a scam, it's better to be safe than sorry.
Best of luck and I hope you continue to develop for the Amiga.