TWiki does not violate GPL

No, TWiki's method of requiring registration before handing out the application, and source code, is not a violation of the GPL. It is unorthodox and unpopular to some people, but not a violation.

A long discussion of this policy and its reasoning is ongoing at http://twiki.org/cgi-bin/view/Codev/NoRegisterDownload

For people who do not want to submit any kind of registration there are some workarounds:

1) download an alpha release from http://twiki.org/cgi-bin/view/Codev/TWikiAlphaRelease

2) get the code via anonymous cvs http://sourceforge.net/cvs/?group_id=3657

3) if you use debian gnu/linux: "apt-get install twiki"