a) A world map, a bed, a table, and maybe a training manual.b) Messy room, or at least full of eye candy.c) Cleanly set up, unless a dirty cave would add significance to the story line.
a) As long as the player isn't meant to have an emotion attachment to "the friend", it doesn't matter. Seeing how only the beginner area is going to be reworked, I'd say to just coin-flip the gender.
http://www.youtube.com/watch?v=lC3P3Q71jUI
I wasn't sure as to what kind of mood you'd like to portray in the tutorial area.
Storywise, how does the player get from the "tutorial area" to Jack's farm?
Hmm...well I think maybe it would be easier if players could choose how their room looks before starting the game. For example, in the same part where you create your character, there should be a part where it asks whether you want your room to be messy or clean, and there should also be a part where you choose the gender of the friend that shows up to get you, along with a picture of the friend so you can see what it looks like for each gender.
As far as music goes, I'm not quite sure what it should sound like, but I have some examples of good songs:
Nothing *too* dark at the beginning, something that matches the general feel of the game.
I was under the misconception that you had someone who made music specifically for Icyworlds.
I'm sorry but this seems a bit vague and unspecific.
Here is a list of various songs and the mood that each portrays.