yeah i have the same thing in my sportivo. im actually relieved to find that i'm not the only one who has it... but now after vigorous water tests i have found my source of the leak. tail gate bolts, the panel beater didnt seal it properly so its leaking. but those points that are leaking, mine leak thru there as well. as for the grommet thing. yes there is meant to be one there. but even so, it STILL leaks from there. i was told my a repair integrity check garage that i shouldn't use a gerni or high pressure hose on the car. and if i do, dont spray into the gaps otherwise it will leak. i havent had any problems since... edit: we also tested out on dyslexik's car and the same thing happened. his car has never been rear ended. same leaking points and entry of water. although luckily we both havent had rust in our cars yet. my car hasnt been rear ended as well but the clips have been reused. one solution would be to use a bit of windscreen sealant around the points of entry to stop the water leaking inside.