CC Disappears at a distance

If you share your package file with us we will be able to check for certain but have you made sure the cut numbers are correct when you import your meshes? Sometimes the different LODs use different cut numbers and so you may need to make seperate meshes for each LOD.
The easiest thing to do would be to export the mesh from EACH different LOD and add the knife to it. Then import them back in. Don't forget to update the shadow meshes, too.

If you have only made changes to the LOD0 then that is your problem right there. LOD0 is used for when the camera is close up to the object and then the object gets swapped out for the lower detail LODs as you move the camera further away.