Nabudis was one of the tougher areas for me to muscle through. I was in the low 40's, but I had a pretty elaborate gambit system, which allowed for me to basically let them do their thing and manually blast the foes with some aeroga or something, when it would get hairy. I had them casting bubble/ protect/ shell/ bravery for tanks/ faith for casters/ and haste. High MP costs, but there are enough enemies to regerate steadily upon attacks and kills. Those stupid ghosts washing out all my mp one by one were a pain, too, but I managed to only use 2 or 3 ethers start to finish. I'm just trying to figure out what the deal is with the secret merchant. Did you have any luck with that? I'm not happy about the stupid medals, either, but I gotta get through those doors.