Issue with trigger changing the state of a button to allow learner to take quiz--Storyline

Hello, all!

I am having a problem with a button not changing from "disabled" to "normal" when all of the required buttons are clicked.

I have a "topics" slide (1.7) with 6 buttons/topics that take the learner to each corresponding section where they view content and do activities/knowledge checks.

In the middle of the slide is a "final quiz" button that defaults to "disabled" and is supposed to change to "normal" after the 6 topic buttons are clicked.

I'm using "T/F" variables for each button, and once the last topic button is pressed and all 6 variables are "True" the quiz button is supposed to change to "Normal," appear transparent, and be clickable to take the learner to the quiz slide.

I've uploaded the file and am hoping I can get some help.

Thank you all in advance!

Chris