Download the latest and greatest sources of BXE including the demo application from the demo site. The files are constantly updated, therefore it's worth watching this space
To use it, just untar/unzip it into a directory and call the bitfluxeditor/index.html file. Either via a webserver or directly from the filesystem. Please read also our wiki, if something is not clear.
The SVN Snapshot package has almost always the latest stuff from our developement hence it may or may not work. The numbered releases are known to work and are only updated if we fix a serious bug in it.
At the moment, we recommend using the SVN snapshots (bxe-snapshot.tgz), or the latest 1.0.x release.