Just a some quick comments on your questions, though the more experienced
will probably comment also.
When I got my Ferret they sold me the Marshall Farms food.  After  reading
about what food to feed them, Ferret food being a popular item, I watched
and noticed he was eating very little in my opinion.  I shortly after tried
some Friskies that my parents had for a cat they had been watching, he just
loved it.  That's when I changed to Iams Kitten food with the occasional
science diet mini-bag mixed in.
 
Ferratone; no comments as I had a hard time finding Ferratone and when I
finally did I add a couple of pumps on his entire bowl of food and mix it in.
 
I didn't have much of a problem with mine nipping but when it was cage time
he generally got ignored until he would just settle down and stare out the
cage, then he got to come back out.
 
You might get issue 1198 and read the post by William Killian, he had some
good information on litters in that issue.
 
As for friends again more post have been done in the past that I have found
useful in my consideration of getting mine a friend.  Have yet to do it
though.
[Posted in FML issue 1240]