Have Next button appear after other pages visited

These triggers on the menu slide will never run, because the variables change on other slides. 

The attached file shows how I'd program this.

• I put the triggers to control the NEXT button on a layer that will "Reset to initial state" when revisited. There's also a trigger on the base to show the layer. There's nothing on the layer, so it's invisible to the user.
• The triggers on the layer run when its timeline starts, which will happen every time the user returns to the slide. Those triggers control the NEXT button with conditions that check the variables that indicate whether the other slides have been visited. 
  • You'll see that my trigger changes the NEXT button to Disabled instead of Hidden. I do that because it keeps the button in place, which prevents the lower navigation items from moving around. 

You can find more info about using invisible layers to run triggers here: TIP: the Incredible Power of Invisible Layers - Articulate Storyline Discussions - E-Learning Heroes

You can find more info about controlling the NEXT button here: TIP: Controlling the NEXT Button 101 - Articulate Storyline Discussions - E-Learning Heroes