I have the same issue here. He hops to the left, then to the right, then to the left, to the right, etc. Even while moving from one place to another you can see him turning left and right. Doesn't do anything during combat or social but will do special abilities and eat. I don't want to kill them for the same reason. I'm trying to stay in the middle, but to do so, I absolutely have to make friends with this last tribe.
Edit:
Ha! I left the game running while I was posting the above. I went back and noticed the leader wasn't hopping any more. Went back and was able to perform.
This is the creature.
http://www.spore.com/sporepedia#qry=usr-ChristianSkunk%7C2263357786%3Asast-500069528623He has one leg and three arms, one on his back, two sharing a shoulder joint under his mouth. When I started, he had two staffs, one in the top hand and one in one of the bottom hands. When I was having this trouble, one of the staffs had disappeared. When it was working again, he had both. *shrug*