<< I wonder why that 3D pdf worked for you and the other did not. A mystery.
yes colors of gears are dispeared on the first PDF as like the light keep them in shadows and kill colors! :)
Ask if its the same for other users!

<< You are right, the animation is not interactive.
just making sure ;)

<< However one can rotate the model, which stops the animation, and then re-start the animation looking from a different ange.
I expect that you are already doing this - just making sure
Of course! ;)