Linux Repro: quit Slickedit. Open Slickedit, click the tab for the hidden "open" tool window. The divider resize handle between the files pane and folders pane is drawn partway up the file list pane. It is operational. If you mouse over it the mouse changes to the double arrow for resizing, and as soon as you click on it and move the mouse the split between panes jumps to the location of the mouse. After that it stays put after opening/closing the "open" tool window. Once you quit/relaunch Slickedit it's back to the wrong location.
Mac repro: different behavior. The handle between the two panes is not operational at all (or sometimes on the horizontal scroll bar), and is not drawn. If you resize the tool window horizontally, the divider handle is then drawn and works as normal. It is not as reliably broken as the Linux version, but 90% + of the time it fails.
Also, while figuring out the repro recipe, I discovered that on the Mac version if you try to quit with "command-Q" it enters a blank character in the File Name field and doesn't quit. It quits normally if the Open tool window is hidden.
-Tim