I cant log to the game either i bought it last night.... are the servers up? or they got shut down orsomething
Did you try the steps listed in the OP? If you are still having trouble after that, shoot an email off to email@example.com and they'll get you sorted. Sorry you're having a problem getting up and running at any rate. :/
edit - also try this. Goto www.demigodthegame.com/downloads.
there are some useful links there for registering, etc.