I don't understand what you want the community to do about this. Seems to me that the issue is between you and phantastisch, and he feels that your translation was sub-par. It also seems to me that if you're going to get paid to do a translation, you ought not make as many mistakes as he claims you made and the ones you admitted to.
If you're truly qualified to translate something, there should be pretty much zero mistakes--if there are, it indicates that you don't know both languages good enough to take on the job. In any case, there's no much anyone here is going to do for you. It's not like anyone can do anything except possibly Theymos, and I highly doubt he's going to get involved in this beef.
I definitely am a good translator, but nobody is perfect, right ? And btw, I never saw an ANN thread which was absolutely perfect, without any mistakes. But you are right, I dont know what the benefit should be of posting this here, but I made a thread in the Beginners & Help section before and they told me to post that here, because I really dont know what to do as phantastisch is the biggest instance in the german local sector, but as I said, he just ignores every argument I write him..