Ok. Thanks for the replies all. Bike is stock and has the original crud catcher still attached. The brushed steel looks like it needs maintaining and will try a high quality polish
The "stuff" on the exhaust is definitely coming from the paint flake. I have managed to get a better picture and it shows that the particles are sprayed over other parts also
You can see the arrowed area to the left of the exhaust in the second picture
The dealer is picking it up tomorrow for first service so will raise it with them and see what they say