Code
KForge development is hosted on http://www.knowledgeforge.net/ and its main page is http://www.knowledgeforge.net/project/kforge/. which provides links to the associated svn and trac services as well as other relevant project information.
The svn repository can be found at: http://project.knowledgeforge.net/kforge/svn/
The trac service can be found at: http://project.knowledgeforge.net/kforge/trac/
You might also want to join the KForge developer mailing list development list which is for discussion of the development of the KForge system.