There's no cure for crazy. At least that's what people keep telling me.
Oh, wait. Crazing.
None that I know of - once the paint starts to crack, about all you can do is prevent it form cracking more. If it were some kind of damage on the outside of the plastic, you could polish it with Novus. But I think what you're talking about is like, the layer that the paint is glued to is starting to change, right? So it appears as if these marks are all inside the plastic. Is the paint itself cracking, or are you just seeing lines in it?
Either way, I don't believe there's a fix. Someone prove me wrong - if there's a cure for this, than maybe someone can help me with my crazy too.
-Ian