Getting the dealer to guarantee a buy-back might be the best thing, if not then its got to be a different colour, do not go the repaint route as if, as someone said, it becomes widespread then you have a car worth the square root of fk all.
I have to agree with Nigel, John and Ben on this one as you say yourself you know its there, add to that if this colour becomes a public issue as already stated it will be almost worthless secondhand.
Also bear in mind that whilst the dealers are being accommodating now, they are going to be far less helpful once they've got their hands on your folding...