It seemed to me that every time it went sideways, that new vertical had no upper parts to that tree. I wish i could diagram it here, but it seems this one was well-formed. I often check, and after 3 times this happening, I trusted the storyteller. I can' guarantee that another writer wouldn't do this differently as I don't know the tech, but this one seemed well-constructed. Did you not look and see that when you were clicking down and it went sideways to the right, there was no up option on the next slide?