Using Variables to Control Slide Advancement

Hello!

Still figuring out all of the cool things that Storyline can do and I am not sure if I am using variables correctly.

I have four buttons that I want the learner to click on before they can advance to the next slide. The button states are set to change when selected to display some additional content. However, because of this I can't get them to stay as "visited" and use that to control slide advancement.

 

I thought I could use a variable. I have added a variable to count the number of clicks. In the trigger wizard I have a condition to advance to the next slide if  the "CountClick" variable is greater than or equal to 4 clicks  (4 buttons I want them to click on). When I test it doesn't seem to be working. Am I thinking about this the wrong way or missing a step someplace?

 

Thanks!