Ok, I managed to do it. I am using the Default-Horizontal layout. I took the default-horizontal.php and got ChatGPT to change the order of the items, making the registration appear before the login. It works fine.However, ideally I would like this modified php to appear as an extra style choice in the cblogin advanced options layout choice.
If I copy my php file and rename it to something else and upload it, it doesn't appear as a choice in this list. It would be good if it could, as I assume the default-horizontal is in danger of being overwritten in a future update.
How can we make a modified php appear as an extra layout choice in the cblogin module? Thanks
P.S. I will attach the modified file, just in case someone else ever wants to do this