When Lawrence checks into the hotel in Reykjavik he is told by the clerk that he is in room 5021. However later when he and Gina are walking down the hotel hallway to the room they go to 5121.
When Lawrence leaves for the lunch date he removes his tie and loosens his shirt. When he arrives at the restaurant he has the tie knotted and proper business look.
G8 Summits are only held in the G8 nations - Canada, the US, Japan, Russia, Germany, Italy, France and Britain. A summit would not be meeting in Iceland.
When Lawrence arranges with Gina to meet for lunch, he picks a date that he is free, suggests a restaurant, and they agree. But they do not choose a time to meet.