I'm doing the last two chapters together so you guys'll be caught up with my reading. When I said we were almost done I was referring to the section of the book that deals with the actual Gospel of Mary/Protoevangelium of James. There's still more of the book.
It's the morning of Zacharias' murder, only no one knows that he's been killed yet. The other priests are waiting for him to come and bless them, but of course he doesn't come. Eventually, getting nervous, they go looking for him. One priest enters into the sanctuary where Zacharias died and sees congealed blood beside the altar of the Lord. Then a voice rings out: "Zacharias has been murdered, and his blood shall not be wiped away until his avenger comes." This scares the crap out of him and he runs back to the other priests.
Seeing as how there's strength in numbers, they all go in and see the blood, and then from the ceiling panels of the temple comes the sound of wailing and the priests rip their clothing in mourning. Zacharias' body is missing, and his blood has become as hard as stone.
They mourn Zacharias for three days and three nights and then choose Simeon to be his replacement.
The final chapter is just a statement of authorship, really. It says: "Now I, James, wrote this history when an uproar arose upon Herod's death in Jerusalem, and took myself into the desert until the uproar had ceased. I glorify God, who gave me the gift and the wisdom to write this history. Grace will rest on all who fear our Lord Jesus Christ, to whom be glory for ever and ever. Amen."
The authors note points out that it is unlikely that James would have written this work at Herod's death in the year AD 4, when Jesus was still a small child. Ancient Christians were also skeptical about this, which may have been one of the things that kept it out of the Bible. They included the Epistle of James, which comes from the same author, supposedly, and they found this gospel useful, but the two were not considered to be on the same level.