One the the things the Trailblazer "ant confiure" target does is to work out some relative paths for the trailblazer configurations. It uses ant to inject these values into the configurations using a filtering copy process.
It's currently coded to work based on the project structure as checked out from SVN. This structure is different to that encountered by the script when run from a distro download. The script needs to be modified to accomodate both structures.
If this script is getting replaced for the 4.0 GA release by something like izPack, we can zap this issue.