Extension: External Registration Form Submission
This tool will allow user registration on external URLs and non WordPress sites. Forward form data to an external non WordPress URL using HTTP POST method. Useful for integrating RegistrationMagic with numerous other web apps.
WordPress Registration Plugin
This extension is part of RegistrationMagic Silver. Note that RegistrationMagic extensions are part of bundles; extensions are not available (or sold) individually.
External registration form submission extension is available here.