So, I believe this is probably out of the realm of possibility for Element 3D (and am therefore about ready to give up), but I figured I might as well post this for the sake of conversation and perhaps helping someone else out down the road.
I am simply trying to animate several animated lines (keyframed spline extrusions) that are tracked to a 3D rotating globe/earth (see: http://i.imgur.com/vOa8oi7.png). The lines need to converge on one point (Dallas, TX), so, obviously to maintain the path, both the starting and ending points need to be fixed. I know several ways to do this in C4D, but, after a few days of searching, watching tutorials, etc., it seems that this may be impossible to do within Element 3D. The most promising method was generating a 3D null and tracking the animating lines to that, but I could not get that to work so well either, as I couldn't find a way to lock the starting point to one 3d null and the end point to another (perhaps some AE expressionist could help me here).
Not sure what difference it makes here, but just before anyone asks... I am working on a late 2013 trashcan, updated to Sierra, 64GB of RAM, 3 GHz 8-Core Intel Xeon E5, Adobe CC 2017, Element 3D 2.2.0