Rotate objects face to camera

Hi all,
I’m new here, and my english is not very good.

I am creating a generator molecules.

When I add a triple molecule want to face the cylinders always stay ahead of the camera.

Attached a picture!

I’m rotating the molecules with ITween, like this:

     switch (number) {

         case 1:
             if (count == 0)
             iTween.RotateTo (connection, Vector3 (0.0, 0,2.0);
         case 2:
             if (count == 0) {
iTween.RotateTo (connection, Vector3 (0.0, 0,2.0);
             } else if (count == 1) {
iTween.RotateTo (connection, Vector3 (180.0, 0,2.0);

And I have a function that updates the rotation of the double and triple molecules.

With 2 molecules already got an interesting result. But with 3 onwards was not good.

Attached project too. [|19753]

Thank you very much.

Why not to use usual transform.Rotate ()? Place everything your object in one main (some kind of container). That to make it, create empty GameObject. Its position (0, 0, 0), rotation (0, 0, 0), scale (1, 1, 1). After it is possible to rotate the created container, at the same time rotating cylinders and spheres.