When you try to recover a lost or forgotten username or password with RC2, you can fill out the form but you can't click on the send confirmation email button at the bottom of the list. You can see the button, but can't click it.
Correction... if you click on the password checkbox first and then the username field then you can't click on the submit button. Also, I didn't receive the confirmation email after I did successfully submit the form.
This issue has been addressed and fixed in Community Builder 1.2 RC 3, like all other known issues, and is available now for a last short rounds of live site testings, before CB 1.2 Stable release.