Custom Next button

Hello,

Here is the scenario.  I have several button on the page which link to layers.  I want to remove the player buttons and create my own next button, which should be disabled until the learner visits all the layers.  So I have variables set for each layer which default to false.  When timeline starts, I am telling the variable to change to true.  Then, on my main page with buttons, I set the trigger to change the state of the next button from disabled to normal when the variable changes to true on all the layers.  Well, it doesn't work.  The button remains disabled.  Does anyone knows why?  There must be something with layers because I had the same set up where buttons were linking to scenes and everything works, the button changes the state to normal.

I appreciate feedback regarding what should I do to be able to execute this on layers.

Thank you, Anna