This is mostly a bug fix release, with big improvements in IMAP export, fixes in XML export and other smaller bug fixes.
You are downloading Wammu source code. Before you can run Wammu, you need to have installed python-gammu, Python and wxPython. There are also some optional requirements for additional features which are listed in INSTALL file in sources. This file also contains more detailed instructions about installing Wammu.
You are downloading standalone Wammu installer for Windows. If you want to use your system Python and install dependencies manually, please use pip tool to install Wammu.