1) Click the "downloads" link at the top/left corner of this page;
2) Look in the "Tutorials" section (third from the top);
3) Click the link for the "Game Design Tutorial2" (A6 WDL Game Templates ~24 MB May 2007).

The download file is called "template6_e.zip" for the English version or "template6_d.zip" for the German version. Inside the zip file is another zip file named "T6tut1c.zip". The cbabe.mdl is located in this zip.

This link should also get you the English version: http://server.conitec.net/down/template6_e.zip