I have been using yarp's P3dO Explorer for Poser and the included python script instead of the P8 library but recently decided to try out the new SR3 option of viewing the library as in P7.

However, I can't seem to be able to expand the tree view.  When  mousing over the division between tree-view and folders the cursor turns to the one shown in the red circle but clicking and dragging as in most other programs has no results here.   Am I doing something wrong?

I'd like to be able to expand the tree view as over the years the stuff I have accumulated has found its way into subfolders of subfolders and it would be helpful to instantly see the whole name instead of the tiny little display of the path when you hover over a folder. Not to mention the fact that not even the refresh symbol can be accesed next to the selected folder now (as you can see only a small crescent shows). 

Besides, since the cursor does change on this particular area one would assume it's because the tree view should be able to be expanded in width, right?

Any help or insight would be greatly appreciated.