As for the weird tiling: go to maps.google.com and zoom ALL the way out. You'll see the exact same effect, only with our earth. Unfortunately I didn't map the stretching at the poles and google actually handles that in its map coordinates.
As for the weirdness in the export of the images...the text being choppy and things like that actually is how the png originals turned out. Now, I imagine that if I used a different less flashy font, it would probably be easier to read, but meh...I'm not really worried about it too much since this is just a proof of concept at this stage.