Here is what the seller stated when I asked him some questions about his CD set that he is eBaying:
"Has every GM bulletin up to 04/01/2004. Has all GM service manuals up to now. You need no password. Is a stand alone software. Does not work online. Just install and go. If you need updates for the future as they come out I will let you know. If the base software gets changed in the future you will have to update to the new base to receive more updates."
HTH
SpottyJ
P.S. - I just bought a set from him today, we shall see how encompassing soon.