tangency beetween MESH Objects

I must solve this problem>

From a pre-exhisting folder, several MESH objects are to be imported and may be available on Rhino screen.

These MESH objects have continuous `surface`, and for this matter can be think as MESH spheres or cubes...

They must be positioned along a poliline on a polisurface, alligned longitudinally to the line and tangent to the surface (normals).
Some Slider (or other control knob) must be placed in order to slide the mesh along the line, allways alligned and tangent. Each mesh with its control.(max 45 meshes)

as the meshe slides when commanded by the user, it must `colide` to the MESH next to it on one side, so, it would become tangent to the neighbour mesh.

any clue on how to make them tangent to echh other???

I could manage to alingn them so far but with `deconstruct BREP`, but it doesnt work the same with `Deconstruct MESH`!!

Need HELP URGENTLY!!!