As you know Astfin is GPL licensed. We are using SVN repository to keep the source code.
If you would like to browse the repository please take a look at http://astfin.svn.sourceforge.net/viewvc/astfin/software/astfin/
To get a copy of the trunk version of Astfin 2.0 for example you can execute (assuming you have SVN client installed on your computer)
svn checkout https://astfin.svn.sourceforge.net/svnroot/astfin/software/astfin/astfin2/trunk/ astfin2