I don't know a whole lot about Paso's, as I've never owned one, but I've been on them before.
Maybe you could go back and do some ground work. What gaits are you trying to get the horse to do?
Maybe you could do some lungeing or ground driving, that way you could look at the horses gaits, get the owners help, see what's good/bad about the gaits, etc.
Maybe you could try the snaffle while doing some ground work.
The world is best viewed through the ears of a horse.