Timeline screenshot is very small, so it is not very clear. However you do have several shape buttons (green lines) which are interactive objects. I can see faintly the vertical hairlines that indicate pausing points. They are all set to the default value of 1,5secs. This means that the timeline is paused at 1,5 secs from the start of the slide by 4 out of 5 shape buttons. The fift shape button will not appear neither, because its timeline starts afgter 1,5 secs.
Read this blog post, and you'll understand why I see lack of understanding of the timeline as the number 1 cause of many questions on this forum (you are not the only one today):
Challenges for Starters - Captivate blog
I presented about the Timeline at the Learning Summit in Las Vegas (2017), will even have two presentations at DC in April 2018. This is the interactive version of my presentation in LV:
Captivate's Timeline