Images disappear at end of slide's timeline

Hi,

I have a slide that is acting quirky. All of the static images on the slide are flush against the end of the timeline-they're supposed to be seen throughout the animation. But when it's published, some of the images disappear. If I manipulate the length of the timeline, making it in increment longer, still keeping everything flush to the end, all of the images disappear a split second before the timeline runs out, leaving the user staring at a blank screen instead of the scene that should still be there. 

Here's a demo:

http://ajlearningworks.com/test/story.html

Arleen