Sorry to hear that, 20 mins before and its gone! That really is bordering on madness. If it is booked to leave at 6, it should wait for everyone to turn up and leave at 6. None of this 'our schedule is just a suggestion' malarky ala cayman airways. I find a few Euro airports confusing for some reason, they always seem to be quite old and maze like (never been to DUS though, i'll keep that in mind!...). Recently went to/from Zurich. Got off the tram from the city, and trying to find where Ba check-in was...crikey. Up stairs, down stairs, over there a bit, over here a bit. Maze! Then getting to the E terminal i think it was for the LCY flight, hang around the check-in terminal with no working ATMs for a few hours after being denied lounge access (status pending after qualifying flights couple of days before), flight finally shows on the board as leaving from terminal E, down stairs, passport check (oddly the same woman that checked my passport coming off the LCY flight a few days before, remembered me as well for some reason), another trip on a train with some weird graphics of a rather pleasing swiss girl supposedly called Heidi or something like that pretending to blow you a kiss as the train goes through the tunnel, more stairs and into a completely empty terminal... If you didn't leave a good 2 hours, you would have no chance if you were not familiar with the place.