It is an enthusiastic fan community. Fighting Fantasy used to be huge in Hungary in the early 1990s, and zagor.hu is keeping the flame alive now that the gamebooks are no longer commercially available. I suppose it's not exactly lawful, but it is a non-profit site, and I hear the work they do is very high-quality (i.e. they have fixed a lot of shoddy translations, including the infamous Crown of Kings fiasco, and translated/are translating those volumes which never made it to Hungary). I do not personally know the people involved.