Hey guys. This is the post I found when I was looking for directions to access my waterfall dishwasher from Samsung. I took some pictures for the next guy.
My problem was a broken chunk of glass made its way into the impeller. Careful with the bottom flap. It has some little tabs that could break easily. The last movement once you've popped the bottom is to flip it up.
Also the pump, grab it and turn it clockwise and then pull out. Your model might be different. But that's what mine was. And yes, you have to put it on its face, so put a blanket down and drain any water out with a sponge and bucket.