One of my older (english) convertibles had a leaky top, no surprise there, and it would build up some mold issues. I just took some Dry Eaze when I stored the car, and that seemed to suck it up.
Question: Does stubby invalidate warranty? Can't imagine it does but BMW are STICKLERS for the rule book, I already asked stealers to re-paint my rusty hubs and they said no. :|