I've just met Barbas the dog in the "A Daedra's Best Friend" quest. I understand he can be exploited as a follower. Unfortunately, he doesn't seem to want to follow - he just runs off ahead and disappears. I also don't see any option to interact with him - "Talk to Barbas" does nothing. Am I doing something wrong here or is this a bug? And will I find Barbas In Haemar's Shame, or is he gone for good? It would kind of svck if I went all that way and then found out I couldn't complete the quest :/

He should be in the dungeon. The game is easy enough that you don't need to exploit him as a follower. If you're having a hard time killing stuff lower the difficulty, or hire an actual follower.

IIRC when you first meet him, you are supposed to follow him to Haemar's Shrine. You can do that right away, or meet him there later, but he's not really following you at all at that point. If you run after him, yeah, I think he'll probably tank anything in your way, but if you lose track of him he's not going to come back to look for you - he'll just continue on to his destination.

After you get the next part of the quest is when he'll start to behave more like a follower, assuming you want him along. If you don't you can tell him to go away and he'll just be waiting back at the shrine.

That's how I remember it anyway.

I've had this. Enter and exit Haemar's Shame, then fast travel between there and close to wherever he is stuck.

With me he got stuck on the walkway above the gate in Helgen, that you first enter in the opening sequence. After a couple of fast travels he eventually became unstuck and got his dialogue back.

You need to follow him to CV not vice versa. After that he follows you. Fair warning tho, his nose will be permanently buried in your backside.