Hello again AndrewJazz,
I do not know if the size of the file is the barrier, I suppose it could be. The file I can get it to work with has a bit over 200 pics, the one that was working up until a couple of weeks ago has a bit over 600. So it is roughly 3 times the size, but it was working fantastic. Operative word being was, lol.
Also, at this time, if I am not using the smaller folder, I found that NONE of the provided files for wallpaper, that Apple provides will work. If I try to change to one of those, it just fills in a color of its own choosing. I mean WOW, lol, eventually it will default back to the sequoia trees, but it cannot use any of the provided pics, so it truly has a really stubborn bug.
It is amazing to me that apparently no one is overseeing the proof checking on software for such a basic part of the operating software, and further more, that those same people still have jobs.