Layer is disabled after timeline ends

Hello,

I've created a tabbed folder interaction following this tutorial: http://community.articulate.com/blogs/david/archive/2013/12/30/how-to-build-folder-tabs-interactions.aspx and it works great--EXCEPT that when previewed or published, a user cannot re-visit a layer once the timeline ends on that layer. I'd like them to be able to go back without having to leave the slide and return to it. I did make one change to the folder tabs--I used a Visited state, in place of a Disabled state, to see if that would fix the problem, but it didn't make any difference. I've tried editing the layer properties, but none of those sound like they would disable a layer at the end of its timeline. I also posted the question in a comment on the tutorial, but I'm not sure if those comments are moderated the way these forums are.

Incidentally, I've also disabled the Next button on this slide, until all of the tabs are in their visited state. I did that using the instructions at this tutorial: http://www.articulate.com/support/storyline/how-to-disable-the-next-button-until-users-finish-interacting-with-a-slide

Thanks in advance for any advice!