blanius,
In order to use the skins km provides, and to call on those skins thru scripting. You need to setup a skin image. When you open the script editor and select the fourth icon - Symbol library. A class window will appear. You will need to select the image tab. Then select add to open a file dialog. Select the path provided above. Once you select the file a class name dialog box appears and you enter the button_png for the name.
Once that is done, when ever you add a class like the LabelButton to your script and provide the setSkin('button_pgn#4,4,10,10', false) code it will reference the XP skin.