After posting that and thinking about your situation I was afraid that what you are seeing would happen.
There is no easy fix from the script side, no way to delay the script wile it waits for all the file to be written to the folder being monitored.
The easiest way to work around this is at the Aperture end. Have all images imported by this workflow go into one holding project, say importsWaitingForFinal (or whatever you want) and then move them from there in Aperture to their final destination project.
If you described your workflow in more detail a different solution might be suggested.
I also suggest you start a new thread for this, you're likely to get a wider audience for the post.
regards
Message was edited by: Frank Caggiano - Ok that works too!!