On the letting the friends know:
You misread my post, or it was unclear. It isn't that you don't want your friends to know what is going on. What I was saying is don't try to get them to hang out, just so that you can get a girl. Make the event something that they will enjoy. It is perfectly fine if they know that you are throwing the entire thing to have an excuse to hang with a girl. You want the event to somehow describe you, and what you enjoy. It builds value when you take the girl to do something that you will mutually enjoy, and that your friends also appear to be enjoying.
On the close:
Unless I further elaborate, a close, means anything where you have physically left no room for doubt, in her mind, that you like her. That means, at least a kiss. However, you will likely need to progress to at least heavy petting or sex before Christmas, if you truly want the attraction to have a chance of surviving the break.
On her boyfriend:
It sounds like her talking of the boyfriend was more a reflection on her crappy night, than a hint that she has a boyfriend. You were correct in ascertaining that it was an inappropriate time to attempt any so called "
Boyfriend Destroyer" technique (I hate that term).
Since you are working on a tight deadline and you are about to burn out anyway, if you don't get a break. You might consider playing the game, high stakes. In that case, be more direct about hanging out with her. The worst she can do is blow you off.
Building
Kino, is about building physical
Comfort. Be careful that you don't frighten her, too much, when you do it. Kino is especially powerful, if you can catch her eye, and then deliberately touch her in some manner.
Don't worry too much about sitting next to her. If you make a point of sitting next to her, it will look like you are chasing her. Move around, just try to chat with her every day, since you have made a habit of it.
I don't have much to say on Girl B, just keep it light and fun, and you may turn it around. Don't let her peg you in the friends category without making her work. In other words, just because she has decided you are friends, don't start acting like a friend. Keep gaming her lightly. Don't be a shoulder to cry on.