Question UI Buttons With No Controls?

[Old Blevins]

I have a fair amount of experience with VAM and using UI trigger buttons, but have downloaded a few scenes that I can't figure out. They have UI buttons that have no visible controls. I can't find them in the Select menu. I can't find any plugins that appear to be controlling them. I can't delete, move or alter them. Can anyone enlighten me on how these are produced and how I can edit them? An example is the free Simple Animation 1 by Oronan. It's an elegant little scene that shows me a huge hole in my knowledge....

 

[atani]

It's simple, the atoms are marked as hidden

Spoiler: Open Select, click "Show hidden", and...

 

[Old Blevins]

Doh! (Hand slaps forehead). Thanks!!!