What's in a name, Severus Kalkaros?

I've just read Pollomuhku ja Posityyhtynen, written by the Finnish translator of the Harry Potter books Jaana Kapari-Jatta. In it Kapari-Jatta talks about the process of translating the novels, the complexities of finding suitable translations for Rowling's neologisms, decisions about which names to translate and hoping that a particular judgement call on a translation doesn't destroy crucial hints or plot developments in subsequent books.