>I don't know how to set the behavior of the treeview to autoexpand !??
>(only the first node is shown and users have to click a lot to expand all nodes)

See treeview's EXPAND services

>Is it posible to do a drag and drop within the treeview ??

Download #16575 has a treeview like "movebar" feature to drag nodes from one parent to another. Check the code inside the examples treeview class definition for mouse + shift down event.