Amazing program, have to try it out myself, might find some interesting spots, maybe an ocean or a big flatness, I also wonder how my towers and bridges will look like. o_o
I also think whoever has a map generator screwing up on them has deleted their world before.
Also yeah, firesmelt is down, try using Dropbox or something.
And I think that the overlapped sections of the map occur if you started a new map or deleted an older one.
Also in your mediafire download it doesn't include the world 1,2,3,4,5 files. Not sure if it's supposed to be like that.
E: Wow I'm an idiot. I just remembered you're supposed to click the world you want to render, and not the cartographer app file. So yeah, remember to click the world file and not the cartographer.exe file.