impossible to make a joint beam

Hi every one, here is my problem:

On the first picture you can see my model.

In this model I would like all the point I put in red on the second picture, to be joints that let the rotation free in all the space's directions. (on the pictures no mouvement is free at those points)

So I set all those points into a "point" component that I logged on the "beam-joint-agent" component, putting on Rx, Ry, and Rz. Then logged de "beam-joint-agent" component on the "assemble model" and I flatten it.

After that it seams that the upper beams that form a square grid are no longer acting in the system. The model show me results like if those beams doesn't exist and let them floatting in the air as you can see on the last picture.

Please help me, this is for an urgent school project,

Thank you