Extruded 3D image brought into video time line. I create keyframe at start and end of sequence. The end keyframe is the default position. I click the key frame at the start of the sequence and manipulate the image to the desired starting position. The keyframes at the end, although not selected, magically change to the new position. So frustrating.
Also, timeline does not recognize alpha channel. I have to create an additional layer with a chroma-key green background.