How to save the opened nodes in dtree?

Suite and Optimus Suite 5
#1
  1. How to save the opened nodes in the tree in the XML and reload them again when I refresh it or whenever I open the tree?

    2) Can I load any single XML element to the tree?
#2

a) tree supports ( pro version )
tree.saveOpenStates()
and
tree.loadOpenStates()
commands , which allow to save|load data in|from cookie.

b) while xml correctly formed - it may contain info about any subset of tree’s elements, which will be added to existing tree after such xml loading