Philippe,
Welcome to the forum. You should find all the answers that you are looking for, here on Kitelife. There is a great deal of knowledge here, and people are very willing to help. Just ask...........
As for the B2, I have 3 of them (Std., Mid-Vent, & Full-Vent), as seen in my avatar. None of them came with weights, and unless they just started including them, I don't believe the B2 comes with weights. That is something that was included with the 1.5 B-series, and honestly, I don't think that many people ever use them. I'm sure someone else will chime in on this.
As for the rods, I am not real clear, as to what you are asking, but, there should be three rods, that make up your leading edge. One rod should look different than the other two. The odd one should go in the center, and the other two are inserted into each end of the center rod. If you are not sure how they go, take them all out, and lay them on the floor. It will be pretty obvious, how they fit together. Once in the kite, you must pull on the end caps, from each end of the leading edge.
Good luck..........