It actually uses Google to translate the pages, and I just read that Google has decided that auto-querying them to do that is against their acceptable use policies. Can't confirm that though.
I'm a translator. I've tried many automatic translation tools. None are close to good enough for any purpose other than getting a general idea of the source text. And even then I've seen many times when that general idea was completely wrong. It's a surprisingly difficult problem to solve and it varies dramatically from language to language, cultural context being such a big part of it. I think selling any translation software borders on being a scam so I wouldn't recommend it. Use the free tools as a start and then hire a translator if you need better.