could not pin point the oil leak without seeing the car myself......but i would check you have a good seal on the engine cover....missing bolts or slack will allow fumes into the cabin....just a thought
......when i had a landrover it ponged of ep90 gear oil.....if i bought one that didnt i would start to worry......if you are not losing noticeble amounts of oil and it passes a mot....then theres nothing to worry about apart from the smell