Just to clarify, I have set up a multisite: eg. http://www.originalsite.com
I have one multisite installation: eg. childsite.originalsite.com
I have installed this plugin and domain mapped the child site to a new domain: eg childsite.originalsite.com === newdomain.com
Everything is working fine EXCEPT uploads to the media library. Using newdomain.com/wp-admin/upload.php (the media library) all images are uploading with a file path similar to: http://childsite.originalsite.com/wp-content/uploads/sites/2/2016/07/test-logo.png The media library is displaying the broken image icon.
If I search for http://newdomain.com/wp-content/uploads/sites/2/2016/07/test-logo.png the image is uploaded correctly and displays.
The major problem is that I cannot edit images or utilise the customiser or media library due to this issue.
Any ideas please?