I think most translations are quite reasonable. I couldn't have come up with a better translation for IGG than Blutzoll, and the Loan-Lohn thing was done knowing that it's wrong, but it fit the picture, and "Kredit" feels far too modern to put on a Dominion card.
What annoys me most I think is the translation of Salvager. I mean, really? Müllverwerter??? Ok, Salvager CAN mean something like that, but this feels so wrong looking at the picture...
My translation for IGG would be "Schwarzgeld" or "Judaslohn" or "unrecht' Gut". Blutzoll is just wrong.
I can't think of a German word for "Familiar", didn't know before long that there is a word for "animal companion". My stab at Familiar would have been "Gefährte".
"Lohn" fits the picture, I have no qualms with that.
What I like about the German version is that all upgrading-type cards (expressed in verbs in English) end in "-bau". Wonder how long they'll keep that up. I think they will bend in on "Procession", but Überbau (
http://en.wikipedia.org/wiki/Base_and_superstructure) would be a nice, if liberal, translation. A real blunder is the Dutch translation to "Remake", which is something like "Version 2.0". It should obviously have been translated with a verb.
A more literal translation to "JoaT" would be "Hans Dampf in allen Gassen" (Hans Steam in all alleys), "Lebenskünstler" (bohemien, bon vivant) fits the picture though.
"Minion" would have been better translated with "Günstling" or "Hofschranze". "Lakai" is closer to "Lackey" in meaning.
Oh yes, and "Dark Ages" should have been "Finstre Zeiten" (bracing for a cease and decist by Friedemann Friese) or "Harte Zeiten" ("hard times").
"Kerkermeister" does its job with the picture and gives a good cue to an old Erste Allgemeine Verunsicherung song.
I can't really think of a good translation to "Salvager", maybe "Bergung". ("Berger" would sound too much like a surname, there is no tradition of having verbs as card titles in the German version so "bergen" doesn't fit, and "Schatztaucher" next to "Perlentaucher" would be too bland.)
"Pferdehändler" has similar connotations as "Horse Traders". You can even insult a used car salesman calling him "Pferdehändler" or "Teppichhändler".