1) GPS MAPS: I cannot install Mapsource
If you downloaded the free link from Garmin to install Mapsource - and it gave an error during the installation informing you that you have to have another Garmin software product installed on your computer in order to complete the Mapsource installation, you can try to install MapInstall first, and then try to install Mapsource again:
Click here for the download link to MapSource in order to install it:
2) VIDEOS: Installing T4A GPS Maps – Mac
3) VIDEOS: A guide to installing MapInstall on your Mac computer
4) GPS MAPS: WHAT IS GARMIN BASECAMP AND MAPINSTALL AND WHY DO I NEED IT?
Garmin BaseCamp is an application which enables you to view Garmin compatible maps on your Windows PC and Macintosh, do route planning and transfer waypoints, tracks and routes between your PC/Mac and your Garmin GPS device. This is a FREE application from Garmin and it will eventually replace MapSource.
Garmin MapInstall is also a FREE application which enables you to transfer Garmin compatible maps on your Windows PC and Macintosh to your Garmin GPS unit. Note that MapInstall is a feature incorporated within Garmin BaseCamp too.