fiddled with the settings and discovered that "yes, no, no" allowed the black background to be expressed. Don't ask me why.

Huh! That's sort of counter-intuitive, isn't it? I can't explain, but I'm glad you worked it out!

It was fun experimenting!

Yes, I did some poking and prodding with mine, too. And enjoyed it.

I still love having a Nine/Jack header but I'm also happy to know that I can change it whenever I feel like it.