// ActionScript 1
var fileName = _root.path;
if ( -1 == fileName.indexOf("%25") && fileName != "" )
{
_root.loadMovie(fileName + ".swf", 0);
}
[...]
// ActionScript 3
var path:String = new String();
path = ( root.loaderInfo.parameters.path ? root.loaderInfo.parameters.path : "" );
if ( -1 == path.indexOf("%25") && path != "" )
{
var loader:Loader = new Loader();
loader.load(new URLRequest(path + ".swf"));
addChild(loader);
}