Trace a path of a photo

Hi

I would like to “trace” a photo in flash. I have done this before but then I had to update every 5th frame or so, in order to get the result I wanted. Is there any easier way to do this? Almost like motion tween a long a path, but with tracing.

Here is the result when I updated, frame by frame:
http://hem.passagen.se/pvone/trace.swf

thx

Appreciate the help