WEll About question #1.
Seeing as how the keet is new, it is probably just nervous and will come out of it's silent shell soon enough. As far as it knows, it may be in danger, and by cheeping it may give it's location away to preditors....
Give it time, and i am sure you will get more singing than you barganed for
it was like that for us with Milo. He was quiet for a few days, adn now 7 months later, We can barley watch TV becasue the 2 of them are chirping up a storm