How to change your ROSIE username or password?

Is there a way to change your ROSIE username or password?
http://rosie.rosettacommons.org/signup lets you set up a new account, and
http://rosie.rosettacommons.org/password_reset lets you change your password,
but the new password is chosen for you and sent to you in an e-mail,
which isn’t the most private way to do things.

Could you make a page more like http://rosie.rosettacommons.org/signup
that lets a user change his/her username or password?

It is also strange that I needed a separate account and password to access this forum about ROSIE.
Why not have one account and password do it all?

Thanks!