The Brizy Local Demo (download and install on from our Github: https://github.com/EasyBrizy/Brizy-Local-Editor) has a limitation in place.
You can test and demo Brizy Local and even integrate with your system, but you will not be able to output the HTML files that you create with the builder. You need a license for that. The Git is meant to allow you to take care of all integration work up front, test and figure out your use case, but to properly use the builder in production you'll need to contact us and pay for a license.
Here is how you can unlock the full functionality in Brizy Local.