Mini TOC

Mini  TOC is a new option in Framemaker 2015.

However, if I am in a structured file, and I go to Special > Table of Contents

the Create Mini TOC option is grayed out and unavailable.

It is my understanding that Mini TOCs should be available in both, Structured and unstructured Framemaker.

Why is the option not available?

How can I make it available and use it?

Thank you.