In response to Leezyjet re: interior pic of door... if by 'cracked' you mean in the 'cracked position'... my guess is, this was done after landing.
If the door had indeed opened (even a bit) in flight, the crew may have been able to use a device on the 747 (restraint strap) which is designed to keep a door in the 'cracked' position should the need arise to vent smoke/fumes from the main deck... again this is purely guessing and may not have been possible AFTER a door is opened/has come open but I would hazard a guess most 747 crew would have had this thought cross their mind as a way of possibly securing a 'faulty' door - or one which they couldn't fully close???