1) Click on the town where you need the Grail, press the spacebar, and go to the buildings tab. Then, you need to find the desired building and highlight it in bold (click and check the "build" box). The Grail is supposedly one of the special buildings, but I can't say for sure which one.
2) Yes, it should be possible. The Tear of Ashi is buried on the map only once, but there can be as many buildings in the town as you want.
3) You need "Random_town".
4) I know that "random_building" can be synchronized with random towns. It's possible that towns can also be synchronized with each other, but I haven't tried it myself. You also need to open the town settings with the spacebar and take a look.
5) A monster? Try it. Set a random monster, press the spacebar, and see what happens.
6) You need to set the corresponding task; read the FAQ for this section for information on tasks. "Defeat after n days" is one of the standard tasks, and it's in the list of tasks.
7) This task is activated by default; just don't change anything.
8) Unfortunately, I can't help with that. Perhaps if you describe the scenario and what you want to achieve in detail, someone might be interested and write it for you. However, based on my experience, people either don't have the time or have their own unrealized projects that they prioritize.