Cary,
Thanks. Your post prompted me to delve a little deeper....
I had created my original 3d curve by highlighting edges on a model and then using "Extract 3d Curve". It appears that IC makes some sequence assumptions as to how the edges are to be connected. The starting point of the curve also appears to be random.
These assumption not only show up in the animation profile but also in the XYZ data of an exported step file (Extract_Trace.png) displayed in a program supplied by a motion controller vendor.
If I create a 3d curve by picking points along the desired edge, the animation profile and starting point reflect the desired results, as does the exported data (Pick_Trace.jpg).
Extracting would be much easier and more more precise than picking points.
Enhancement request: "Extract 3d Curve" retains pick sequence and start point.
Steve