Thanks in advance.
While not exactly what you are asking for, you could use the Curve.PointAt method.
Set the curve/s domain to 0-1, then
ptOnCrv = Rhino.Geometry.Curve.PointAt(crv, t)
Beside @chanley brilliant solution, you can also use Curve.NormalizedLengthParameter:
success, t = crv.NormalizedLengthParameter(param)
a = rs.EvaluateCurve(crv, t)
IVELIN PEYCHEV.gh (13.9 KB)