For some reason, your on_motion function didn't work for me. It didn't even enter in the function...

But never mind, I decided to make another approach using a variation of your code (clicking in the image bring that pixel to the center of the widget).

But I have another question, if you don't mind: clicking in the arrows of the D-PAD cycles the focus through the widgets of the app. I want to use the D-PAD for better purposes, but it keeps moving the focus, even if I do some "...grab_focus". How I completely disable this focus cycle properties of the D-PAD?

Thanks a lot!!

L.