Well the tip of the plug is clean so it's not coming from the cylinder.
Possibly coming from your the rocker cover and seeping down into the spark plug hole.
If your under warranty i'd get the garage to check it out, because there could well be a crack in the head? unlikely but you never know unless you can find out where it come from.
But i'd say it's the rocker cover gasket..
Our mk3 vr6 did this but i just ignored it, as it wasn't a big deal....
I don't own an r32 but i just come into the forum to see what's what with theses engines, because i'll probably get one pretty soon because i'd like 4wd plus i'm missing the sound of the vr6 engine..
I have a 1.8T turbo which i'll still keep but it would be nice to own a big engine again before they completely throw the big engines into history and the only purr noise we get is when the engine is misfiring
I suppose the 2.5T engine purrs so that's probably what we will be stuck with, on saying that petrol will be so dear i don't think we will be driving cars in the future, back to the peddle bike!
I hope you get it fixed..