Username has an "_" in it and "_" is not supported. What can I do to remedy this.

As of right now, the username to the game, and the username to the website do not have to be the same. they are housed in two different databases. right now, I would set up your profile on the game without the underscore. That way you can participate during the alpha. Once the two databases merge, it might pose an issue (in which I'm sure you will not be the only one). They may have to change the scripts to allow underscores and other non-character types in order to port over everything. The last part is purely my conjecture though, as I'm not on the development team.