To unpack the files there is the free program 7zip.http://www.7-zip.org
BTW, my download was sometimes at 25 kb/sec
Thanks for the feedback. I have downloaded the 7zip and the installer is corrupted!
Having said that I have just managed to dl the second set 4-6, this was after two goes and Stuffit unpacked it just fine.
So hoping that I can eventually get the rest aok all I need is the Intro movie from the first set But I do still wonder if it would be best to have single files to dl?