Same problem here guys. I was down 1 bar on the weekend (I waited for the bar to show it low by 1 bar for 5 consecutive days simply because it continously changes). I added 350ml of oil, and the display then showed that I had overfilled (all bars inc. the one above max.) I drove the car for around 5 miles in Sport mode and really smelt some burning for the first 3.

This really worries me. The car is now showing all but the top overfill level, but I'm wondering if the burning smell is anything to worry about. I've driven 250 miles since then and all seems to be ok. I hate not having a dipstick!