Looking for help, I loaded the winni map onto my Garmin Nuvi 500 last week. I don't seem to be getting any detail, all I see is a brown outline of the lake and a boat icon, there are no markers shown at all. I does give gps position but that's it. I've been in touch with Garmin tech support with not help. Is there a trick to getting it to work that is not in their instructions. Any help would be appreciated.