Yes, the registration is for free.

Did you register an account? You have to register an account in the first place before you can login. If you are already registered but you still cannot login please check your user name and your password.

No worries! You can get a new password. Please click "Forgot password?" below the login button. Follow the instructions and you should then be able to login again.

Your own data can be easily and quickly changed under "User profile".

Using incorrect or false information or an inappropriate user name could be reasons for the rejection. Email addresses such as spam@xyz.com or xyz@thrashmail.com are also inappropriate.

Yes, you can. The option to delete your account can be found in the user profile.