Podiom is the map in the back of your character when you're creating your character. And Sky Rim, I know how to get there, but I don't know how to explain it. Go to Acension Island and start on the square platforms, once you get to the circle platforms, go left. And somewhere up the circles, there should be platforms going down, go to those. And they should lead you to the ring platforms that lead you to the Sky's Rim portal.
Hope this helps!
~~Alaskan~~
