The Mapinstall patcher works for me Win7 x64, btw you can patch MI manually comparing files in Hex Editor.
Mapsource is discontinued, Garmin doesn't support it anymore. New City Navigators maps selected and created with MS can give routing problems in gps, many topo maps are not visible or don't show properly in MS. Don't use it anymore.
Basecamp (+Mapinstall) replaced Mapsource and it is the recommended and actually developed software for Garmin mapping.
