Checking your DirectX in Technical Preview....

I've read stuff from Paul Thurrott and a couple of geek websites on how you can find information about this, by going into your "Search" and typing "dxdiag" and following something from there. Didn't work for me. Here's what does:-

Press your Windows key with R on your keyboard, and in the little Run box that opens, type in dxdiag.exe and click OK.  This opens the DirectX Diagnostic Tool.

On the first of several windows or pages, you see the main system information including near the bottom your DirectX version number, in my case, version 11.
The other 'pages' accessed from tabs along its top just under the title bar will tell you if there's any problems, and if those say "no problems", you're OK. You can exit the Diagnostic Tool and enjoy programs using DirectX, like Stellarium.
And an "Expert" is defined as anyone more than 10 miles from home...and God still helps those who help themselves.