Yayfray program?

I downloaded yayfray. I have trouble locating opening the program? I read the notes in the notepad… but nothing works

What do you mean? Locating or opening it?

As for the first, the “program” or merely all the files which make it, are located in the directories you have specified during the installation.
As for the latter, there is no real Yafray program, you could open. You can access it via selecting “Yafray” in the drop down button in the Render Tab and use it to render your scene with Yafray. Or, you can also use the commandline to start a renderjob. But there is nothing like an editor or something, which you could actually open…