GraFx is being ironed out but I would check the BMP to see if it's really black
"CTK" error (Chair To Keyboard, i.e. user error)
It was the first thing I checked, since it seemed the most obvious that I hadn't made the pixels completely black (RGB,000), but sure enough, some of the pixels were set to 3 instead of 0.
Thanx Erv. Glad I was diligent and took your advice.