Try parenting the light (say) to the mesh. First move the light to where you want it in relation to the mesh, and then:
EntityParent light,mesh
Now every time you move or rotate the mesh, the light will move as if it's a part of it! Particle emitters are trickier, and depend on the system you're using, but it's essentially the same thing.
EntityParent light,mesh
Now every time you move or rotate the mesh, the light will move as if it's a part of it! Particle emitters are trickier, and depend on the system you're using, but it's essentially the same thing.