I checked with the .NET team (I work at Microsoft). I did not like the random behavior, some machines install fine, some do not.

As Crion pointed out, Control:PC needs .NET version 3. Turns out, Windows 8 includes both v.3 and v.4, but only v.4 is active. The OEMs (the computer manufacturers that deliver Windows-based computers) and some corporate IT department may choose to activate it -- this is the reason for the apparently random behavior.

If the Control:PC install fails on your machine, you can just start Control Panel, select Programs, then Turn Windows features on or off, and select .NET 3.5 (on my machine it is the first item). No need to download it.

I think the same thing applies to the Config program.

Music room: 818v3, DSP8000SE, Roon/Intel NUC, microRendu/LPS-1 into Geek Pulse Xfi into Audeze LCD-3
HT: G61R, HD621, MS600, Oppo, Avantgarde Solo
Library: MS600, Bel Canto, Mark & Daniel
Other: SonicOrbiter, GeekOut, Audeze EL-8