Basecamp and Edge Touring Plus

Hi, I would like to plan a tour with Basecamp and transfer it on my Edge Touring Plus. The only problem is that, when I try to create this plan, maps installed on my Mac are very basilar, and if I connect my Edge Touring Plus, it starts reading the installed Garmin Map on its SD and it is fatally slow (I think it takes about 15 minutes).
Is there any way to locally install Garmin maps on Mac? If there's a better way to plan routes, you are welcome. I was used to plan them on Bikeroutetoaster, but it doesn't seem to work anymore :-(
Regards