Lister background image gone, "Use for lister scrollbars" option Grayed Out - unavailable to enable

About 48 hours under my belt as a happy new D.O. user, and I find myself once again in need of guidance.

I had D.O. setup and working well for about 24 hours, then without warning the background image for the dual listers went away and was replaced by the "File display background" color. The same background image is being used successfully by the toolbars and Folder Tree.

Although I wasn't tinkering when this occurred, I'm sure it was some esoteric option I inadvertently set.

Attached is a screenshot of the grayed out option and a couple other Preference dialogues I thought may have overlapping effects such as the "Use visual style."

I reinstalled D.O. 12.6, which changed nothing. I toggled the "Use visual style to draw items..." option, which didn't change anything (other than what was expected with the mouse over high lighting, etc.). Additionally, I "Restored" previous configurations from several backups taken throughout earlier today and yesterday when I know D.O. was working fine, and are not working now. I'm out of ideas.

Any and all help and direction is greatly appreciated!2017-10-07_23-23-1023

Well, I spoke too soon. Now the background image disappears with almost every typical activity such as scrolling, copy and pasting files, changing folders, etc. and is replaced by the "Preferences > Colors and Fonts > File and Folder Colors > File display background > background" color. I can go into the "Preferences > Display > Images" and reset one of the images and the background image will return. I am baffled.

This is after totally uninstalling, reinstalling D.O. and deleting and reloading the background image.

The "Use for lister scrollbars" is still active and working as it should.

Help would be greatly appreciated.

An update:

After totally uninstalling and re-installing D.O. once again, then while setting tab colors in the LEFT lister, automatically the RIGHT lister's background image changed from the desired current image to the previously used older image. Inside "Preferences > Display > Images" the File Display image was correctly set to the new one in "Standard File Display Image." I change the setting to a different image and back to the desired one to enable and click on "Apply" and the background in the right lister returned to the correct image.

To eliminate this behavior, I have deleted all other images and now have only one image used for everything. I am keeping my fingers crossed hoping D.O. doesn't change the lister file display background a color again.


Another Update: 2 Hours later

So far, so good. After removing all images except for the desired one, and selecting the same image for every "Standard" image, things have settled down. No more automatic image changes so far with 2 hours of continual typical file-related activities (renames, deletions, editing, etc.). Will report immediately if any odd behavior occurs. Otherwise, I will provide a final report after 24 hours of "up time."