The package is 9gb in size? My guess would be that if the package is actually that big, you might be hitting a timeout for the download. Alternatively, if you are downloading it rather than running from source, is it possible that the target machine does not have enough space on the drive where the sdmcache directory is located? Another thing may be that your antivirus does not like one of the files and is preventing the copy. as an example, Autorun.inf is one of those files that a lot of antivirus software will prevent from being copied to a share.
Timeout is unlikely, we have other packages that take longer than this one without a problem.
Disk space on the target computer(s) is fine, but I'll see if the Antivirus has anything to do with this.
Well, problem solved. It wasn't the Antivirus program after all.
That specific file that would stop the task suffered from one of the oldest entries in the book I think : Full filename + full path was too long (over 256 characters). Swapped it around a bit, shortened some folder names and it's fine now.