Storyline 360 | Disable and Enable a close button on a Layer

The trigger that disables the Close button runs every time the user returns to the layer. ("When the timeline starts on this slide/layer" really means "When the user visit this. slide/layer.")

There are two options for better control:

• Add conditions to the trigger, so it will only run if any of the buttons ≠ Visited. 
• Simplest: Delete that trigger. Instead, set the Initial state of the Close button to Disabled. 

Also, be sure the Slide Layer Properties are "Resume saved state." 

By the way, you don't need a trigger to change an object to its Visited state. That happens automatically when the object with a Visited state is clicked.