How can I add files to an event in the marketing calendar?

Via the 'internal links' section in the event overview.

• Navigate to the marketing calendar via Communication > Marketing Calendar in the side navigation panel. 
• Create a new event or select an existing event to edit.
• Scroll down to the "Internal links" section and click "Add link".
• In the pop-up window, click the ‘+’ in the actions column to select one or multiple items
  

  • You can link to: assets, products, categories, pages, blogs, and packages.

  • Use the search bar to quickly find the desired item.

• Click "Save" to close the pop-up, then click "Save" again to apply all changes to the event.