1. It would take about two months or so. Remember that Kyurem is being met with the resistance of Alder(who survives), the gym leaders(most of them survive, more on that later), and other very strong trainers. So it would take a while.
2. Yes, but no killing actual people while in the duration of the game. You can kill NPCs though, no gore please.
3. See above. Also someone can die in your history. No gore is allowed as it is rated T.