Under my Plan Details, why does the top Progress bar show "Complexity Attribute Not Defined"?

Using RTC 3.0.1.2 with the Formal Project Management Template.

I am looking at a Plan page. The Plan Details are expanded and there is are 2 Progress bars. The bottom one has Progress: 24/112 | -16 h, Estimated: 100%, and the bar is properly filled in with red and green. The top bar has Progress: 0/0, Estimated: 100%, and the bar has no color and says 'Complexity Attribute Not Defined'. The bar's tooltip says the following:

"Missing Configuration
Complexity Attribute is not defined. Open the Project Area editor, select the Process Configuration tab, and navigate to Project Configuration > Iteration Plan > Work Item Complexity Attribute to select a work item attribute which stands for complexity."

When I open the Project Area editor, there is no Process Configuration tab, only a Process Description tab. It does not have a Project Configuration setting nor does any other tab in the Project Area editor.

Is this Complexity Attribute only enabled for SCRUM projects?

If so, then why is there a bar in my Formal Project Management project that shows this error message?

If not, then how do I fix configure my project area so that this message goes away and the bar displays some helpful information?