I have a question about the ransacking ability. In the rules it states "Each time you successfully conquer a Region containing an opponent's active Race token, he must immediately pay you 1 Victory coin from his own persona stash (unless he has no coins left)."
Does it mean that you can only ransack regions that have one, and only ONE token?
No. If it did it would say something like "containing exactly one token of an opponent's active Race". Saying "an opponent's token" just means there's a token there of an opponent there, but sets no limit to how many. So, each time you conquer a region occupied by an active race, you get to take one of their coins.
I am asking that because in the spanish rules it says something more like "1 opponent's token".
Yeah, that is one of the difficulties of translation -- the subtle inferences that exist in one language but not the other, so you can introduce ambiguities, or eliminate them in favor of the wrong interpretation.