It depends on a combination of your Navigation Restrictions, along with what triggers you are or are not using.
The simplest way to accomplish what you're describing is to:
- Set the Navigation Restrictions to Restricted AND select "Lock Next/Previous buttons"
- DON'T add triggers to change the state of the Next button (Otherwise your triggers are fighting with the Navigation Restrictions setting)
When the timeline starts, the "Lock Next/Previous buttons" setting causes the Next button to be disabled. Then when the timeline is finished, it automatically enables the Next button. When the learner goes back to the slide later, the Next button is still enabled because you don't have a trigger changing the state.
