I activated the CMC plugin for Community Builder to appear on the registration form. Now when someone wants to register for my site and does not check the box for the newsletter, he will be unable to proceed, as the email textbox is required. This is however not visible. It only becomes visible that the textbox is empty when the user checks the newsletter box. The field mappings are active:
EMAIL=email
FNAME=name:0
LNAME=name:1

On the other hand, I tried to solve the issue by not showing any fields, and relying only on the field mapping. This works at registration, but causes a problem on the user profile of Community Builder. If the user did not register for the newsletter at registration, he will be unable to do so on his user profile. It will result in the following error when the user hits subscribe:
"400: The resource submitted could not be validated. For field-specific details, see the 'errors' array."

Please help. Thanks!