Remake questions

I’ve seen every scene (and the secret preview) so no worries about spoilers for the blue moon content. But if something is explained in red garden then just say pass.

1. What’s with the prologue? Somebody (probably akiha or either shiki) goes into the woods, a “stranger” kills everyone (so not the father). Then it’s never actually explained?
2. Why does Arc hate Ciel from the start? She’s willing to work with some executors (or at least not kill on sight) but singles Ciel out. Is it simply because Roa possessed Ciel previously?
3. Where did that book go in Ciel route, when shiki is tearing the room apart? Was it even real in the first place, or is Roa screwing with shiki’s memories?
4. In the path where Roa takes over and already killed Hisui/Akiha, why is Konoha so calm? It is later revealed to have been a few days so Konoha would definitely know by then, on account of the sister’s patrols (and you know, general awareness). I’m assuming it’s related to her “machine look” in the waning moon bad end.

I fully expect a lot of passes here, but I’m just wondering if I missed something. It feels so odd to have so many plotlines set up and then just… not elaborated on at all. I can wait for the second half to be remade for that (hopefully soonish).