Download this package: http://www.microsoft.com/en-us/download/details.aspx?id=8109 Then run it, extract to accessible directory, open this directory, find and run "DXSETUP.exe" installer. After installation finished try to run launcher once again.
So you tried to install if using exactly this installer? Any other DirectX installer likely would fail to install required libraries.
I tried the installer you suggested from other recent posts and that one, I also restarted my computer but I have made no progress.
Actually it's would be interesting if some other player on Windows Vista would say if launcher work there because I not sure especially about 32-bit Vista.
Well, the system requirements on the website says it's supported so, yeah. http://www.uberent.com/pa/2013/06/26/mac-and-win-32-play-now-on-alpha/