The Windows XAMPP installation of the Rasa Quickstart worked like a charm. All K2 features, including User Groups, Extra Fields, and Extra Field Groups are accessible right out of the gate. :cheer:

So, the issue is with the Linux installation only. :(

Is there anything in the LAMPP configuration files that could affect K2 User Groups, Extra Fields, and Extra Field Groups access?

By default I'm using:

owner.group is apache.apache
directories: 755
files: 644

As an experiment I did try chmod -R 777 on the entire site to see whether it would make any difference to displaying these K2 features, but no luck, so fixed the permissions again.

Thanks!