This is the tutorial CEP.

It contains various examples of action, component, application and viewer extensions. This source code gives you a good insight on how to develop with the CamiTK SDK.
While these extension are not useful for end-user their codes is provided as "How To" write CamiTK extensions. The other Open-Source CamiTK CEP is also a great source of practical examples.

You can also check:
* The CamiTK wiki, another good source of information: https://forge.imag.fr/plugins/mediawiki/wiki/camitk/index.php
* The SDK, imaging and modeling CEP.
* The API documentation: http://camitk.imag.fr/apiDocumention.php

And more generally, check the website http://camitk.imag.fr for the latest news and update.