Could be the clearcoat. I always back mine with black faskolor and dont realy have a problem with the finish. If anything you put on afterwards has the SLIGHTEST hint of a solvent in it then it will kill the finish of the shiny chrome look.
I normally do the chrome when there are a couple of layers to go in the job, this way it puts a couple of coatings of faskolor on the chrome. (this only works if the colours after the chrome are faskolor).
I've done this and backed it in custom colour nitro block, and it has kept its chrome finish. the faskoat also works without disturbing the chrome too (just a thin coat, not too thick)
Hope this helps dude.
