Thank you for the reply!
1. You previously had a full working version on your old 2011 MBP and you now have a newer MacBook Pro running Mojave, but HX Native fails to run correctly, as shown in the screen grab?
Correct!
2. When you swapped over to the new MBP has it ever worked correctly and now simply stopped or it has never worked on the new machine?
Helix Native has never worked correctly on the new machine.
3. When you swapped over to the new Mac did you do it by "migrating" from the previous hardware, or was it a complete fresh start.
I did not use data migration - all programs and plugins have been freshly installed.
5. Did you de-authourise your old computer and then authorise the new one?
Yes, I had deauthorized my previous computer.
6. Have you tried a full uninstall and re-install of Helix Native?
Yes, I have uninstalled, restarted, installed, restarted - no dice.
7. Did you go to your Line 6 Account page a verify that computer is actually in the Authorised Devices list and Native is listed on the Activations page.
Yes, my new computer is an authorized device per my Line 6 account page (additionally, my previous computer is deauthorized.)
Thank you again and I hope this helps to clarify my issue!