Although Flora-2 relies on the XSB inference engine to run, a suitable version of XSB is bundled with each release of Flora-2 and there is no need to download XSB separately. If you are a developer and need the very latest features and bug fixes of both Flora-2 and XSB, you might need to download both from their respective repositories.
Please follow these steps:
This version contains the latest features, but might not always be stable. However, this allows you to track the development of Flora-2 and contribute! You can install the released version and the SVN version on the same system and switch between them at will. The development version of Flora-2 often requires that you install the latest development version of XSB directly from XSB's SVN repository. Under Windows, configuring the SVN version of XSB requires Microsoft's Visual Studio.
Check out the latest version of Flora-2 from its SVN repository into a separate directory and follow the installation instructions. You can download a read-only copy by clicking on the RO button on that page and copying the appropriate SVN command that appears in a window on the right. Please report any problems (and fixes!).
Note: the development version downloaded from SVN is not tested under Windows on a regular basis and has a higher probability of being unstable.