I'm sorry, I have perhaps said it all a bit unclear.
First of all, yes, I have read through to wiki/"getting started" and I have also used a program a bit before. When I said "installed", I meant "not downloaded as a Rar or something but installed by the official installer instead". I do realize that this is the only legitimate source of the program, but I was trying anything to solve the problem myself.
Now about those "portable version" and compatibility stuff. The portable is a version derived by someone out there from the VoxCommando version 4.1.2, run in a some kind of a sandbox, i suppose. So whenever I try to make a Skype call it launches a new Skype instance and throws various errors at me. The reason I used the "windows xp sp3 compatibility" on that odd portable version was that it seemed to enable the AudioEndpoint plugin, which didn't work other way.
Now when it comes to the normal version that I would definitely prefer, I tried installing the same 2.1.4, 2.2.0.9 and the Beta 2.2.1.4 to D:/Programs/VoxCommando which I believe is not a system protected folder. When I encountered the problem, I tried if any of those compatibility params would help just in case.
Oh, yeah, an the .NET version I am using is 4.5.1 (at least that's what would the installer say if I try to install .net).