Version 2.6 has just been released.
Changes in 2.6
* Improved installer/uninstaller
* Custom spam filters using text or regular expressions
* Option to redirect Exchange conduit to a second box (Windows or Linux) running MWES
* Option to ignore MTA authentication and pass all email through filters
Some specific things:
* When you install, it doesn't matter which version you upgrade from - the process will be smooth.
* Uninstall now leaves your user data behind.
* Custom filters: When you come across spam which is not being picked up all the time by the other filters, you can write a custom filter to catch it. Plain text and regular expressions are supported (using the http://www.regexlab.com/en/deelx/ engine). There's a few filters included which you can import and use. If you feel like writing some, we'll include them in a downloadable file for others.
* Run MWES on a different box (Windows or Linux) than the mail server. Allows for scalability. Linux version actually allows many different hosts - we'll add this to Windows in the next version.