All the core addons and most of the non-core addons have examples of their usage. So if you are starting a new project and need to use just one particular addon, the simplest way to do it is to just copy the folder containing the example of the addon into a new folder, rename the folder, and start to change the project's code for your needs.
For example, if you plan to make a project that will use XML files to store the settings in the project, then copy the folder
apps/myApps and rename the copied
myProjectXml. Finally, open the project inside
myProjectXml folder and continue developing it there. The
ofxXmlSettings class is included in the project, ...