All downloads are in the files section under Sourceforge project page
. You can read also the full change log
If you want to get pop2owa through SVN check the SVN page.
There is a stable branch and a developmental branch. Since version 1.0, pop2owa has adopted the same numbering scheme as the Linux kernel, which uses three numbers. The first number indicates a major version. Differences here usually mean that a lot of things have changed. The second number indicates if the release is stable (even number) or unstable (odd number). Finally the third number marks smaller differences between releases.