I'd like to make a Data Field (or maybe an Application) that shows a map or even just the trails of a local area, as simply as possible, on more-basic watches like my Garmin 55. I don't care about routing or navigation. Just want a picture, or just the lines of the area, and a marker that shows where I am. The RouteIT app is similar idea of what I'm aiming at, but I want to keep it much more simple, no-frills... not connected to the dynamic.watch website, for example.
It also would be great to find source code for a similar application that I can leverage and learn from. Someone pointed to this site, which is helpful, but I haven't found much directly related to showing a map (aka image) or trail lines with maker for current location.
Any suggestions on which components would be best to use?