Propel 1.6.4 is now available, and it's the first bug fixes only release.
The release is available on GitHub under the 1.6.4 tag on GitHub, as PEAR package (runtime & generator) and as archives (ZIP and TAR). But this release is also available through Composer: propel/propel1.
Found a typo ? Something is wrong in this documentation ? Just fork and edit it !