Add scrolling bar to seleced state

Hi, 

I am building a slide that has some words in a box. When the box is selected, I'd like some feedback to appear in the box. Trouble is, the feedback is longer than the box and I'd prefer not to make the font of the words smaller. 

                 

I thought I'd simply add a scrollbar, but the insert: scrollbar is grayed out when I am working in states. 

I found a thread about using a slider instead of a scrollbar, but the slider is grayed out when using states, too. 

 

Am I missing something simple here, please? 

Thanks

Amit