Custom icons on Garmin ZUMO 595

I'm using Basecamp on Mac, I create a route and use a number of different icons that represent different locations. I transfer the route to Garmin ZUMO 595, and there are only TWO icons available—an orange flag, and a blue dot. Is there ANY way that you can transfer the symbols from Basecamp onto the GPS unit? I have seen similar posts but they haven't answered this question definitively.