I didn't have any trouble with installing FX.php on a Mac

I have Vista home premium and it is 64 bit. I don't know if that has anything to do with it.
I'm not sure if I did it right and I'm getting a silly problem. The FX folder it says to drop in your web server stays "read only" even when I apply read and write permission to it. And I noticed something else there was a .DS Store file in that FX folder which is for a Mac so I deleted that file but since all the files in the FX folder are text files it should be okay right?I'm p
robably making this too complicated but in the zipped fx.zip download there are two folders and two files. One is _MacOSX folder and the other is FX folder. I assumed the _MacOSX folder is the Mac version and the FX folder is for the pc? It says drop that in your htdocs which I did. I have XAMPP. The problem is there is that .DS Store file in there but I deleted it. I just wonder if this FX.php is for the PC and if so why it has the .DS store file in it? I think all I need in the HTdocs folder is the FX.php class. Is that right. Maybe these two files are for something on the Mac and for the PC all I need is that one file?
Does FX.php work on Vista PC 64 bit?
thanks,