Got the tonneau to fit for the first time and went from Poole to Cardiff with the top down. Think I shall need a hoover!
HAHA! Mine did exactly that! I have been using the tonneau cover regularly since I bought the car 7 years ago with never a sign of the dreaded foam dust. Then one day I removed it to put the hood up and my car looked exactly like this.
As recommended by many, I put the tonneau in the washing machine (twice!) but it still shed orange dust. I have tried painting the underneath with some diluted PVA. I'm still evaluating it.