Nate :
When creating key frames, you have to make them in the masterobject.
First I selected the masterobject in the animationtray, and then created a keyframe. Then I altered the splineobject.
To finetune it: slide the timeline to the new position, make sure the materobject is still selected and then create a new keyframe.
Wayne :
Where is this tool. That is great, didn't know we had something like this in Carrara.