Does not work with multi-page webforms

[laryn]

This issue has also been reported over the years in the D7 issue queue:

• https://www.drupal.org/project/webform_registration/issues/2705253

Using this module on a webform with several pages does not work.

1. If the username and email fields are on the first page, it creates the user and the form becomes outdated as soon as you click the button to progress to the next page. Continuing to complete the form then causes the site to error.
2. If the username and email fields are not on the first page, it will not allow you to progress to the next page as it gives a message to say that an email address is required.

...

PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '' for key 'name': INSERT INTO {users} (uid, name, pass, mail, theme, signature, signature_format, created, access, login, st...

[laryn]

In working through this to try to allow multipage forms, I found things seemed needlessly complex with the way the form keys were implemented. I ended up reworking things substantially to try to use webform component id's instead of the form keys/needles/haystacks approach that was used initially. That said, it's a pretty major change and I'm sure could use some more bulletproof testing. I've put all that in a 1.x-2.x branch but won't make an official release until it's more fully tested but others as well. So far in my testing, it's worked on a basic level with:

• single page registration form
• multi page registration form
• multi page registration form with CiviCRM integration (including credit card payment)

https://github.com/backdrop-contrib/webform_registration/tree/1.x-2.x