Hi, the one I know at the local scrapyard is 3.3 petrol so I could only help with the wing switch, I have that problem with one of my cars, rain got inside the buttons and now the passenger window it comes down but it doesn't go up unless I pull the switch many times and it goes up little by little. You could try removing the switch and clean it with a fine sand paper and wd40 otherwise needs replacing. As per the leakage, try turn the nuts more they might be loose if someone did any work on it in the past and left them loose by mistake,
