Using the installer...

• download the current release in the download section
• uninstall previous versions (English: Start -> Systemproperties -> Software; German: Start -> Einstellungen -> Systemsteuerung -> Software)
• unzip the downloaded file
  • make shure you have Microsoft .NET Framework (at least Version 2.0) installed. If not download it
• run the setup.exe
• the installer will first check the prerequisites and if necessary install them
• restart Word
• check that the menu "Insert" > "Reference" contatins a new item "BetterRef" (german: "Einfügen" > "Referenz") (see Screenshot)

Prerequisite

• Microsoft Word 2003
• The Microsoft .NET Framework Version 2.0
  • included in the installer:
    • Primary interop assemblies for the version of Office you are using (Word 2003) (Word 2007)
    • Visual Studio Tools for Office (VSTO) 2005 SE runtime
      • Visual Studio Tools for Office (VSTO) Language Pack (optional)