WindKun is the in game MP name I'm using from crysiS 1, apparently has no email attached to it as I cannot find any email attached the username and no way of attaching an email to this account.. I already registered my CD KEY with this username and want to register my steam LE MP code but it asks for an email address... If anyone can please help that would be much appreciated!!!

nobody?! how do I add an email to this account?!

Well, I had the same problem, couldn't find out what email I used so I couldn't login, but then it just magically automatically went to the redeem screen when I click redeem code from ingame, don't know what to tell you. try logging in and click "remember me" on the site (if it has one), then exit your browser, go ingame, click redeem code, and maybe it'll send you straight to the page instead of asking you to sign in again.