Drop items directly to the "Object Navigation" bar.
Service Studio
OutSystems 6.0
It would be nice to have the possibility of drop items from the left "widget" bar directly to
some specific point of the "object navigation" bar (I really dont know the correct name).

In complex layouts sometimes it's hard to drop tables, expressions or if's to the expected point on canvas, especialy when it's necessary to drop something before or after a DIV or TABLE. 

Rafael Pereira
If you are editing a page, you can actually show the whole layout tree by clicking on the '<>' button in the very top right corner of the  layout pane. It is hidden, and many people dont know it exists, but allows for much more accurate placement of elements. 
2014-03-07 07-44-05
Arlindo Lima
As Philip said, you can drop widgets in the Widget Tree.

Idea implemented!