9-patch drawable behaving badly, weird artefacts - what is wrong here?

Question

so Im trying out the 9-patch images. I started out with a PNG-file where I have a semi-transparent square with rounded corners:

Answer 1

Make it small as possible. 9-patch cant shrink they can stretch. Fill right and bottom border with black color. Edit 9-patch borders with draw9patch tool to prevent errors. Your 9-patch should look similar to this one.