You can get more information from the ac6-tools website and download (registration required) various documents highlighting:
If you forgot your password, you may request that it be reset. Just click the “I forgot my password” link on the login pane; you will be redirected to a page where you just have to provide either your login or the email you used to validate your registration.
You will then receive a password-reset email, containing a link to click to be able to choose a new password.
If you remember you pasword in the meantime, you can ignore this mail: your password will only be changed if you follow the provided link.
On the other hand, if you do not request pasword reset, this mean that another user (probably with a similar username) made an error, and you may ignore the message: you password will not be changed.
If you forgot your username (or login name), you may recover it simply: just request that that your password be reset by clicking the “I forgot my password” link on the login pane; you will be redirected to a page where you have to provide either your login (that you don’t know) or the email you used to validate your registration (that you better remember...). Type your email and confirm.
You will then receive a password-reset email, containing both your login name and a link to click to be able to choose a new password. But without waiting for th email, you will find your login name in the displayed page, so you can ignore the password reset mail (if you remember your password of course).
If you don’t find help on this site, this is probably your problem is not related to the toolchain or the IDE but to something else. There are several useful sources of information you can look at: