Another reason why i went for full leather on my second MINI R56. I had the same issue with my half leather seats, as the cloth part stains unbelievably easy. If you try and spot clean it, it will look worse every time. The only way i managed to sort stains was to use a good fabric cleaner BUT you must clean the whole seat panel and try and keep it as dry as possible. Whist slightly damp but not dry give it a final wipe with a rolled up cloth / pad.