Scrollable List of Clickable Buttons Problem

Hi all, i am trying to set up a dynamic button menu, by following this guide:

When i get to this step:

I am stuck.

I have created the second BP widget (listItems), but when i cast to it, I can’t connect the output to anything.

What am i doing wrong here? For bonus points, what is the node marked ‘Set the text’ in the tutorial image?

thank you much.