Email

If the account is in fact yours you just click the lost password link at the top. It will email the account. FYI there is a new system that makes it harder to change your email address.

This is the link that you want to use.
http://www.z8games.com/lost_id_password.aspx
Click that and enter the email address you used to create the game account. If you do not know the email then its going to be hard for you to prove that the account is in fact yours.