I configured the registration using joomla and I received the creation of the account on the administrator email and the activation link in the user email. When I switch to CB to do registration, none of the emails are sent.

It might be a missing configuration. Attached some screen shoots

I configured the registration using joomla and I received the creation of the account on the administrator email and the activation link in the user email.

This might help -
In the Community Builder readme file (included with your cb_1_8_0-unzip1st.zip package), it states:

11) Adjust Community Builder and Joomla/Mambo CMS settings to allow registrations
only through Community Builder

To do that, login to the J! admin backend: Users > User Manager: Click 'Options'



On 'Allow User Registration', select 'No'



Then, in Components > Community Builder > Configuration > Registration select 'Yes' for registration