I think the maps from the map pack DLC are 'fixed' maps. (looking at it now)
I've literally seen the exact same tile setup. in the pictures on the map pack store page. as far as 2/2/5? - No, I think it was better than that. I'll have to check when I get home. At work til 5.
Better than that would be odd.....I though the maximum was x+y+z=9
As for tile setups, the maps are generated by stamps. These stamps consist of 5x5 tile areas (I think they are 5x5...could be mistaken as I never paid much attention to this aspect of modding). Therefore, if parts of the map may look similar...it's because they are in fact the same.