Version 3.5 is the last one released. The homepage of the developer does not exist anymore. It seems that version 3.5 is the one that is available for this application.
Since it's an old product, the problem of compatibility rises and there are two cases: the product will not work at all or it will work with limited functionality.
In this case, Windows XP Mode available for Windows 7 is recommended so that you can still use the application in a "more compatible" environment.