I tried your steps. No jy.
Following your lead, I did a variety of the following.
I unlocked the toolbar and tried to save. No joy.
I went through several cycles of different combos, selecting only an icon, not icon and text, exiting at each step and restarting to check the result.
I then tried to put up the Close icon w text.
I /also/ tried at the same time using the File | Exit, rather than the X button.
For whatever reason, I then wound up with 4 Close icons, one w text. I deleted them all but the one I wanted (no text). It is useful to note that the icon image for all of them was the same, despite my having selected different icon images during each cycle.
I then locked the toolbars.
Everything seems as it should be, but I am so very NOT sure what step or steps actually worked. I have exited and restarted several times, and it seems as it should.
~R~
p.s. It's Ninetrees, not Nitetrees, but I appreciate the reply that got me started in the direction of the result that I wanted.