Admin panel not working

[tinkerdudeno1]

I've worked through issue #27, updated my instance and I'm still not able to see the Admin panel, even with a fresh installation. If this was fixed, it might be broken again.
I build using --build-arg admin_is_sysadmin="true"
The error message in the browser console is identical to the one reported in #27: "The controller with the name 'RegisterUsersController' is not registered."

For the record: This project is awesome work, thanks so much for all your effort.