At this stage, no release has been made yet, use the CVS server to download the sourcecode and build all tools locally. (follow this link).
The easiest way of dowloading the source code is via CVS from cvs.sourceforge.net as an anonymous user; Follow the instructions from sourceforge and substitute the module with sourcecode to access the latest versions of our source code. In case just a particular component or file from CSTK is needed, a web-based CVS database containing all source code can be accessed as well (courtesy of Sourceforge.net). Compressed packages can also be found on this site for dowload, but they are almost guaranteed to be old and near-obsolete.