Why can't I get the foundation flail at Marrok's to work. I bash chests with it and nothing happens. Am I doing something stupidly wrong or is this a bug?

Chests have damage resistance on them, perhaps you don't hit hard enough to punch through. Your best shot is use Powerattack or to use weapons that do elemental damage.

Besides, what are the stats of the Foundation Flail?

It casts knock on hit. But unless Im crazy, Bash and Attack are different actions. Try attacking rather than bashing.

It still doesn't work, and I can't get my character to attack a chest, only bash it.