Customized users registration

Hello,
I’m looking for a plugin that includes a form IN THE PUBLIC PART of WordPress that allows users to register, and can customize this form previously by the administrator adding N new fields.
I’ve seen some plugins such as “Register Plus” (or Register Plus Redux) and “Pie Register” which lets you create a custom form with added fields but not for the public part of wordpress but to the previous screen registration.
I’ve also seen a plugin that allows customize users registration from the public as “profile builder” but can not add N extra fields created by the administrator.
Any ideas?
thank you very much