First of all these skins will work with Adobe Flash 8 and up. They will not work on any previous versions of flash.

To use the skin just place the skin_name.swf into C:\Program Files\Macromedia\Flash 8\en\Configuration\Skins.

Then in Flash 8 in the parameters of FLVPlayeback component choose the desired skin file.

I will write a more detailed tutorial on how to use these skins.