The short answer is yes; AudioLabel is compatible with Windows 8.
Microsoft released four different versions of Windows 8:
Windows 8 Pro
Windows 8 Enterprise
AudioLabel should work fine on Windows 8, Windows 8 Pro, and Windows 8 Enterprise. The Windows RT version was designed to compete with the iPad and other popular tablets, and run on low powered devices. The RT version can only run special Microsoft applications that are available from the Windows App Store (very similar to the iPhone). Since AudioLabel is not a Microsoft app, it will not run on the Windows RT version.
I hope that helps. Please let me know if you have any other questions.