Sometimes it will be awfull to link external data to MapPoint, because the join field in mapPoint is the name of territory. There is a match table between french municipality and key code census (INSEE) in five digit (two for départements and three for the municipality)
le blog decigeo
Go to the new titled (Commune MapPoint INSEE) . You can download the excel table.
It will be great if some MapPoint users join to the way to offer a world matching table with official census codes!!!