OK, I really can't find this one anywhere... googled, searched linux questions, ub.. forums, arc... here...
Maybe some insider on themes like Agust or other would happen to know, how to set the backgrounds to resize stretch or center the way I want?
My situation is this:
I was able to have those beautiful backgrounds from themes filling my desktop right in any screen resolution I wanted. They would resize as I changed them and all was nice and neat.
After some - who knows which

setting change - it became all default sized.
So now, if I chose from, say, the original background from Agust themes, be it animated background or a static one, or if I make my own from my imported pictures, it's always the default size of the original picture.
If it's animated or not, If it's bigger than my screen resolution, I noticed I always see only the very top of the wallpaper.
I can see that is so from the wallpaper setting window preview, where all the wallpapers in the system or personal folders are viewed in their own entirety.
But, when I click on the apply button, my desktop becomes either filled with the color of the corner of the chosen wallpaper, or it has a smaller picture than the chosen monitor resolution.
Itried to make a few different size wallpapers by importing.
No matter what I select on the window - stretch - center - resize,... it's always the original size... or in the upper left corner, if the picture is smaller than the screen resolution, or it is NOT viewed entirely, if it's bigger than thee.
I also noticed, that the ones, that are made in the size of the screen resolution I'm currently using, are filling the entire screen correctly.
I added a new user to check if by default it's still OK and there all the settings are working the right way.
So it must be some configuration file in my /home/me/.e/e/config folder. I don't want to just leave it that way. And I don't want to delete all other settings eather, so I'm wondering which one is to delete or replace with the new, for example, from the new added user /config directory.