strange setup for pgcs

I am doing a tv series(thankfully I don't need avisynth). It only has 1 vts and 9 pgcs 1st pgc is a slide show(well just a blank 00:00:00;00 but if still show is shown it blocks the menu appearing) any way the other pgcs 2,3,4,,5,6,7 are 1gig 9 is another still.The thing is pgc 8 is 6.4 gigs(size of dvd basically) thing is that would give a total of 13 gig which obviously isn't possible.Now the menu has the option of playing all episodes.I am aware that this is what pgc8 is and obviously there must be a trick to this,any ideas what to do with it.Iwas gonna just stick in the still from pgc9 but I am now curious how this works having it appear as if its 6.4 gigs when it can't be.I assume somehow it is linked to the the first episode and runs them in order.Never come across that before. Any ideas on this,

Nothing strange at all. The video can be used by many PGCs. PGCs themselves do not contain the video, and are not gigabytes in length (that is the size of the associated vob). The program part of a PGC is a list of cells to play.

Thanks Mpucoder would I use decrypter as normal then??Not sure how to deal with it.