When Max gets to the D3 needing Gemma's help, he is less than 40km from his meeting with the Notaire Auzet. When he gets to the intersection he is facing south and the sun is to his left, meaning it is morning and his appointment was for the afternoon, giving him plenty of time to arrive at his destination. We are shown him by a tree telling Gemma to reschedule and this would not have been necessary.
When Max is trying to reach to his cell phone after falling accidentally in the empty swimming pool, the cell phone is spinning as it vibrates during a call (the cell phone's antenna is towards Max), but in the very next shots, the phone is turned 180 degrees counterclockwise (the antenna is not towards Max).
It is constantly suggested that Max works in 30 St. Mary Axe, one of London's best known recent buildings designed by Norman Foster, which has a radial plan with a strong diagonal diagrid frame wrapping the exterior wall. The interior shots of the firm take place inside a standard rectilinear office building with regular columns. (See Basic Instinct 2 for scenes that appear to have been filmed inside 30 St. Mary Axe.)
About 6 minutes into the film, after Max makes a killing on the stock market, his colleagues burst into a chorus of 'For he's a jolly good fellow', ending with the line, 'Which nobody can deny.' This is the American version. As the action takes place in London, they should be singing the British version, which ends, 'And so say all of us.'