Making an image semi-transparent… Or is that semi-opaque?

[HavingTooMuchFun]

Espermaschine said, "You can get a transparent clipboard brush from a layer with lowered opacity by using the 'Copy Visible' command"... but that's not how it's working for ME. I've tried this with a bunch of different images, and no matter how low the opacity is, the clipboard brush outputs a totally opaque image. Is there some weird setting that's gone wrong here, or some important step that I'm missing?

I'd also REALLY be grateful if someone would tell me how to turn off the brushes and get me back to normal pencil functioning, LOL!