Re: Storyline

You don't need any triggers to require users to go through the entire timeline of each slide in order. Just go into the Player Properties and set the Menu to Restricted navigation. 

FYI: Here's more info about controlling the NEXT button: https://community.articulate.com/discussions/articulate-storyline/tip-controlling-the-next-button-101 

Use the Slide Properties to set what happens when a user revisits a slide. Details are here: https://community.articulate.com/series/articulate-storyline-360/articles/articulate-storyline-360-user-guide-how-to-adjust-slide-properties