It close enough to stable, just make sure you get the drivers for your other hardware. I found it actually best to install windows 8 with a clean install, then instantly upgrade to 8.1, finish any updates you need after that, then install all 8.1 drivers for your hardware.
Also it seems once you set the options on the kraken, that even after you wipe your hard drive it will keep the same settings...This means the software is stored in the kraken???? This could mean you can set it, then re-install windows 8, if you don't want 8.1 that is. This is just what I see, as the color of the led stays the same. Even when OS is shutdown.
I had the same problem. Try looking at each of the Win32 files (dll/exe/msi) within the installation folder and its subdirectories to determine whether it has been blocked by windows.
On my machine, a number of dlls within the Kraken installation folder were blocked. Windows displays a message stating something like "This file came from another computer..." when you view the file property dialog (right-click on the file and select properties)