WMV requires a compatible media player such as Windows Media Player or GOM Player. CBV format requires a compatible chess reader. Commercial options are available and freeware options include ChessBase Light (recommended) and Fritz 5.32. The Scandinavian Repertoire Ebook requires Chess Openings Wizard (COW). The software will convert into COW Lite Version after a 30-day trial of the Express Version, but there's no need to worry about this as the Lite version is able to view the ebook anyway.
Requirements: Windows OS (not critical, but recommended), Media Player, Chess Viewer, Chess Openings Wizard/Bookup 2000, ZIP file opener (automatically comes with Windows XP or later)