Dashboard Stains

I bought a piece of clear window film (flex-o-glass) to cover the dashboard of my new Murano to protect it from my dog's claws. It was left on for several days and when I removed it it appeared the vinyl had darkened slightly wherever there was contact. As the film has a slightly tacky feel (it sticks to itself slightly) either there was a transfer of the surface coating or a chemical reaction between the two plastics. Water will not remove the stain, but I haven't tried anything else until I hear from the "experts." Can anything be done to remove the stain? Thanks. Frank P.S. This is not the same type of plastic sheeting used in drop cloths.