DDJ XP1 - CDJ 2000 NXS - DJM 900 NXS

Hi, I have a couple of Cdj 2000 nxs and a dam 900 nxs and I bought a DDJ-XP1.

First question:

I red the user's manual and it says to connect the pad to the Mac with a usb, the djm with a usb and at the end the cdjs with a lan cable (and so with a hub) to the djm.

It doesn't work.

So, how do I connect each other cdjs djm and the ddj?

Second question:

The djm and the ddj works together (not with the cdjs). In the settings I can select the output of the sample, but just one of the channels, one two, three or four. How can I send the audio of the sample to the main output directly? Because if a song is going on deck 2, but the sample is on the channel 1, I have to turn up the crossfader 1 to play a sample, and so I cannot play the next song on deck 1 because people would hear me adjusting the tempo. And of course I cannot continue changing the output of the sample on the computer every time I change a song. channel 1 channel 2, channel 1 channel 2 etc.

Third question:

On the ddj there are 4 sample banks. Why should I have the same bank on both sides? I mean, If I have opened the first bank on the left side of ddj, why can't I open the second bank on the right side without change the left side in way to have two different banks opened (16 + 16 = 32 samples), one for deck 1, and one for deck 2?

Fourth question (this is a suggestion):

Would be possible to have a sample bank associated for each song? I totally work with samples, so some times 4 banks with 16 sample are not enough and I have to unload the samples from a bank, load 16 different and so on. I think would be great to have the possibility of loading a track and its 16 samples associated, load another track and load 16 different samples.

Thank you.