Creating a custom route on google maps then converting to gpx


Hi All,

New to POI Factory. Enjoying my time here so far. Quick question, I want to create driving directions on google maps and then modify them to my liking by dragging the route around to different roads. I then want to convert to gpx and upload to my garmin nuvi 57. Trouble is I can't figure it out after watching youtube videos and reading up on the web. The gpx files I have uploaded don't act correctly. They show me staring location and ending location but not the route I designed with google maps. I want to be able to create the route and then just click on the title within my GPS and have it take me on that specific route. Does that make sense? I have read that there is a difference between google mpas and mymaps. Should I be using one over the other or perhaps a completely different resource? Thanks for any help.