create a user based on the fields of a published content

Hello everyone,
 the business rule module is a very interesting module for me it has a future promoter but I meet a small problem with this module I would like to explain in a few lines what I would like to do. The scenario is as follows: I created a content type called registration and attached to the native workflow of drupal 8.
1- a logged in user completes the different fields of the registration content and then submits it for review.
2-the registration is subject to a content control according to a defined workflow
3- If the content is promoted to the published status then a new user is created based on certain fields of the published content.

what I can do with the business rule module:
- control the state of the content and create a new user with pre-filled fields (non-variable) if the content moderation state is equal to published

what I can not do with the business rule module:
-Recover the value of the fields of the published content to create a new user on the basis of these fields (variable) and subsequently sent him an email once the account create.
when i try to save with the variables i get the following error message in the log:
The website encountered an unexpected error. Please try again later.

Type	php
Date	Thursday, November 1, 2018 - 17:48
User	admin
Location	http://dmo9h.ply.st/node/3/edit?destination=%2Fadmin%2Fcontent
Referrer	https://dmo9h.ply.st/node/3/edit?destination=/admin/content
Message	Drupal\Core\Entity\EntityStorageException: SQLSTATE[23000]: Integrity constraint violation: 1048 Column 'title' cannot be null: INSERT INTO {node_field_data} (nid, vid, type, langcode, status, title, uid, created, changed, promote, sticky, default_langcode, revision_translation_affected) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6, :db_insert_placeholder_7, :db_insert_placeholder_8, :db_insert_placeholder_9, :db_insert_placeholder_10, :db_insert_placeholder_11, :db_insert_placeholder_12); Array ( [:db_insert_placeholder_0] => 8 [:db_insert_placeholder_1] => 20 [:db_insert_placeholder_2] => article [:db_insert_placeholder_3] => en [:db_insert_placeholder_4] => 0 [:db_insert_placeholder_5] => [:db_insert_placeholder_6] => 1 [:db_insert_placeholder_7] => 1541094533 [:db_insert_placeholder_8] => 1541094533 [:db_insert_placeholder_9] => 1 [:db_insert_placeholder_10] => 0 [:db_insert_placeholder_11] => 1 [:db_insert_placeholder_12] => 1 ) in Drupal\Core\Entity\Sql\SqlContentEntityStorage->save() (line 783 of /home/dmo9h/www/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).

please any help would be welcome. Thank you in advance.