This add on works in conjunction with WordPress Social Login. The Add On adds the [wordpress_social_login] shortcode to Membership Checkout, with the option to manually create the user name and password.
Changelog Details For Nulled Paid Memberships Pro – Social Login Add On - Version .3:
* ENHANCEMENT: No longer hiding the submit button until users login or enter account fields. * ENHANCEMENT: Now hiding the social login options and showing the default user account fields if the user submits the form and there are missing field errors.