Fixed for the Part 2, the stairs looking to the right had incorrect data that doesn't allow the warp block to work.
Yes you can, you've been able to since the Beta 12. Just follow the path behind the PokéMart.
Also, Pika isn't counted as a Pikachu because it's its own variation. Regular Pikachus appear in Viridian Forest.
Those glitches were already reported and I think that there's nothing anyone can do about the amount of PC Boxes. There's little to no research on the subject.
Go catch a Vulpix put it in your party, Interact with the shrine on midnight might be 23:00 - 00:00 on your timezone
For what is worth, I triggered it just fine at 4 AM (
GMT -3, Uruguay).