Zane
I'm not sure what the colours you pasted...
This is a one line web page you can create and
view locally.
...looked like, but this sounds more like Nicotine
discolouration from being around a cigarette smoker.
Possibly. It did smell a hell of alot like paint
when it came off, but showed no dropletting patterns
(was as even as the original finish), tended to be
on the top surfaces (as if from Sun or a precipitation)
didn't look smoky or carbon-like, didn't smell like
cigarette Smoke at least.
Does this sound like Nicotine?
My guess if it wasn't sunburn is perhaps a fine oil
from some kind of manufacturing, it really bound on
to that plastic.
John A.