FYI,
If you plan to install it someplace other than the default location of C:/FreeSWITCH just make sure to update the paths in "Admin, System Settings" from the FusionPBX web interface.
The default username for the GUI is admin, password fusionpbx
At this time FusionPBX utilizes sqlite for its data store. The author, mcrane, plans to release a new version soon with support for a MySQL, or PostgreSQL backend.
regards,
Carlos