Unlocking a custom 'Next' button after user visits each layer

The state change doesn't work now that I look at your slide because if the object is visited and they hover over it again it is changed to normal.

You should use a T/F variable that tracks when a layer is visited. And then when all of the variables are true you can change the state of the continue button.

However, you don't know which layer they're on so you need to add a trigger to account for each variable change, for example, change the state of the continue button to normal when Var B = True on condition that Variables A, C, D, and E are True.

I'd create a simple check-off system to indicate they visited everything and use that.