its was a bug, keep hosting conts until you get random earth. Save the turn 0 file. host new, load game, select the earth. Then cancel the load and host new . It kept the earth map setting, in the same way that it keeps settings after you have been to someone elses game set up.
It doesnt work since recent patch tho as conts doesnt random earth anymore...maybe there is another way round it?
Its a fun map for roleplaying , but the locations are not very balanced and it often produced boring games for USA start and lots of quits.