It's relatively easy to add your own templates and examples to the start page.
To add one of your files to the template list, copy the relevant .capx to the template folder in your installation directory.
Then edit the 'startdlg.xml' in the root folder of the installation directory and add a new template section like below:
<description>Create a jetpac game.</description>
(might be an idea to backup this file before playing around, just in case).
Save and launch C2 to test.