Customisations from View Designer not available in External Template

The Nuxeo Training: Getting Started 9.1.3 external template was recently released with additional customisations made with View Designer:

• Custom document layouts
• SVG icons
• Translations
• Worklflow layouts

When installing the template, however, some of the layouts are inaccessible from View Designer (clicking on the Customize button for the BC Portfolio custom document does nothing) and the resources folder is empty.

The View layouts that can be accessed are added to the resources folder once you try to edit them, but this is not possible for all layouts.

With Nuxeo FT 9.1 registered to the Studio project contract-management-nuxe, it is possible to follow this tutorial. With an empty Studio projet and the external template, the tutorial can't be followed because it is impossible to create the custom documents necessary during the setup.