Simple product images lose sort order when uploaded through "Create Configurations" wizard

[AlekosDordas]

Preconditions

1. Magento CE 2.1.6
2. PHP 7.0.18
3. mysql Ver 15.1 Distrib 10.1.16-MariaDB

Steps to reproduce

1. Admin Panel > Catalog > New product
2. Fill required fields
3. Configurations > Create Configurations
4. Select attributes (ie. size + color) > Select Values
5. At Step3, select "Apply unique images by attribute to each SKU" and choose one attribute.
6. Upload 4 images to each attribute value
7. Change their sort order by drag 'n dropping
8. Click Next > Next and then save the product

Expected result

1. The simple products (that have just been created) should have their images in the sort order that have been set during the Step3 of the configurable product "Create configuration" wizard.

Actual result

1. The simple products (that have just been created) lost their image sort order that have been set during the Step3 of the configurable product "Create configuration" wizard.

Additional information

This also happens if you try to edit configurations of an existing configurable product.
It does not happen when you reorder simple product images from simple products page. It only happens when you reorder images from configurable product "Create Configurations" wizard, or "Edit configurations" wizard, at Step3.

[AlexWorking]

Hi, @AlekosDordas. Based on Your issue an internal ticket was created, identified as MAGETWO-70167. You'll be informed immediately as the bug is fixed. Thank You for applying.