I can only answer 4 & 5.
4. You won't start completely from scratch but your city will decrease in size/tech level, not sure how to put it. This is how I understood it at least.
5. Yes, there will be mages, they won't be numerous (you probably won't be able to have more than a few) but magic in DoF will be quite powerful.
This might be a little silly but I can't help but ask if you made a typo with your nick. I have a nagging feeling that you wanted to use Felicity instead of Fecility.