Looking for advanced Metadata examples

Hello all,

In the course of planning a new Omeka site, we are looking for working examples of advanced MD configurations:

1. Example of hierarchical MD sets. In the tutorial it says: To simulate hierarchical elements in your schema we recommend delimiting the elements with a colon. . Can anyone provide a more detailed explanation of this line?

2. Working Examples of ItemRelations plugin.

3. Additionally, we are looking for a solution to split the display of long MD lists into tabs. Is this something that can be achieved only customizing the theme, or there are easier solutions.

Thank you for sharing your experience.