Hi Tom,
here's a basic nod to move a object along a curve.
Place your object on XYZ origin and name it Traveller.
Creat your curve path can be close or open 2d or 3d and name it Curve Path.
The nod divides the curve path into 100 steps (can be more or less) and the indexselect moves the Traveller
to these positions as you rotate the knob (or switch to auto).
Cheers
Barry