The CTools Plugin Example is an example for developers of how to CTools access, argument, content type, context, and relationship plugins. There are a number of ways to profit from this: 1. The code itself intends to be as simple and self-explanatory as possible. Nothing fancy is attempted: It's just trying to use the plugin API to show how it can be used. 2. There is a sample panel. You can access it at /ctools_plugin_example/xxxx to see how it works. 3. There is Advanced Help at admin/advanced_help/ctools_plugin_example.