Don't know guys. Yes, ICM's plastic is very soft and yes I sanded with 1200 grit very lightly but I have a feeling it was the solv-a-set that sat a little too long at this one point. Probably softened the plastic. If it was my sanding, I would have had to go through a layer of dullcoat, Future, RLM 74, RLM 75 before hitting bare plastic so I doubt this was it.
Anyhoo, will move on and will watch the decal solvent in future. Have yet to do another dullcoat spray and will let you know how it goes.