Not sure what is preventing the downloading of the BIGADV work units.
Is it worth while deleting the log files, and all traces of the work previously done and re-starting the installation with cleared stats on the servers to see if that'll force the re-start. I can confirm that bigadv units (I asume they are as I'm getting jobs that take 3 days to process and they give 80k+ points when submitted! - is there a way to check?) are out there and running fine.