Just type in the email address used during sign up.
The User-ID is this thing that appears in your browsers address bar when you are visiting your own user pages. It looks like this for example: aBc_d6
If you forgot your password, simply use the pw recovery feature to get a new one.
We decided to develop a "multiple username system", which allows more then one user with the same name. I mean, i now 2 Peters with the same surname... So it won't happen that one will get a message like "username already taken". In advance to that, our system allows you to choose any name you want, if it complies with the 8-bit Unicode Transformation Format, this gives you the opportunity to sign up with a fancy looking user name and on the other hand to register with your chinese name etc, just play around. You can change your user name as often as you want in your settings.
