Hey Robert, just paste this in the position expression:
P = transform.position; // layer position
x = marker; // marker
v = 100; // value that you want to move after each marker
n = 0;
if (x.numKeys > 0){
n = x.nearestKey(time).index;
if (x.key(n).time > time) n–;
}
if (n > 0)
d = x.key(n).index
else
d = 0;
m = d*v ; //multiplys marker Index times value
[P[0], P[1]+m]