First, does the Skunk count as a Farm, or Forest Animal? It scores as the Wolf if the Skunk is in the Forest, and as the Rooster if the Skunk is in the Farm. (It feels a bit like the Cylon Sympathizer in Battlestar Galactica.) I lean towards it being a Forest Animal, as those are the ones with unique scoring rules, and otherwise the Skunk would be eaten when in the same Area as the Wolf.
Second, according to the discussion about the English rule for 2nd version with Skunk and Tortoise, it seems as if the Skunk's Ability actually only work on the immediately adjacent two players, that is the players to the Skunk's immediate left, and right. I hope to have this confirmed though. It could very well mean the first player to the Skunk's left, and right which is in the same Area as the Skunk. I look forward to clearing this up.
The Tortoise I merely treat as a Farm Animal, and acknowledge that it's Ability can impact scoring.