Tree Pane - selected item problem

There seems to be a problem with the selected node in a tree pane. To reproduce:

- Insert a tree pane
- Using the property panel, set the selection to the first item
- Click outside of the property panel and notice that the first item is properly selected
- Select the tree again
- In the property panel, notice that the selection is now listed as "None"

From here, it's confusing to reset the tree to actually having *nothing* selected. You must first select some other valid element as the selected element, then you can successfully select "None" to turn off the selection.

Using Balsamiq Mockups Desktop - 1.6.33

Jeff