Issue with Profiles

My mistake. This is not an issue with the module. Just not clearly documented.
Defining which profiles appear in the registration form is done by adding form display modes to the Account Form Display:
/admin/config/people/accounts/form-display

At the bottom under: "Custom display settings" click the "Manage form modes" to go to the "Forms modes" settings and then under the "User" section create a new form mode for each profile with the profile field you need in your form. These modes will then appear in the Multiple Registration form under the select list: "Form mode to render the Register form".