Multiple shapes following a spline

I’m currently making a animation where multiple (50) shapes (Circles) are following a looped spline. To accomplished this I did:

  1. Make a looped spline
  2. Create a circle linked to this spline
  3. Create a duplicate layer running from 0 to 1 with a step size of 0,02
  4. Export the index of the duplicate layer
  5. Connect the origin size of the circle to the index

This creates 50 circles following this spline. So far so good. But my next step is animating these circles to move over this line in a train in a constant speed. My end result is a looped gif.

Anybody who can give me a hint?

I can give you an example instead.
Is this what you’re trying to achieve?

DuplicatedObjectsLinkedToSpline.sifz (2.0 KB)