To give you a very quick introduction on how to use cGPSmapper, below is a small sample to create a very small (and not very useful) map:
To create a ready to use map compatible with Garmin receivers, save the above as a file named Polygon_1_test.mp, or download this file, and run cGPSmapper providing the name of this file as the parameter.
As the result you will get this file:
This file is ready to be uploaded to the GPS (however it might make no sense to upload it since it's very, very small and completely useless map), but if you decide to upload this file to the GPS (or rather you will create your own map), you can use the sendmap program (but only if you have a COM connection to the GPS)
sendmap com1 Polygon_1_test.img
That's all! Isn't it easy?
The Polish Format accepted by cGPSmapper is explained in Test_img.mp file. The last recent version is always available in the cGPSmapper package on the download page.
If you don't know how to start creating sources for cGPSmapper, you can use the GPSMapEdit program. It can simplify a lot of your work.