Black Cat CMS is based on LEPTON v2.0 Alpha, as released in May 2012. (See http://www.lepton-cms.org) After the key developers left the LEPTON Project in May 2012, there seemed to be no more development concerning that version, so we decided to take and finish our work. So, Black Cat CMS is what is called a "fork".
The name "BlackCat" is derived from the forum names of the founders: creativecat and BlackBird.
Official website of BackCat CMS (german only!): http://blackcat-cms.org
To build your unique download bundle with the add ons of your choice: http://blackcat-cms.org/page/download.php