You need to use the stones, then you need to go from and forth from the "End of Time" until all story elements are triggered.
You need to:
A) have enough stones (like... 12, I had 14)
B) have used them all
C) each *used* stone triggers a story-progression in the Homestead, each time you visit there you get a new one.
D) the door will open if you did all A-C.
Last edited by Tripledragon; 11/08/14 11:38 AM.