The Overview pane provides access to the element structure of the STx project file. In the screenshot above, you can see the path to the project on disk and below it a tree displaying the audio files within the project.
If you select an element in the Overview, the Detail displays the content of that element (e.g. if you select a sound file, the segments in that sound file are displayed in the Detail).
An asterisk after the project path indicates that the project has been modified and the modifications have not yet been saved.
The root element of the STx project file is the STXDataSet element. See XML Structure for more details.