Well having used it for months all of a sudden- today- I have a band at the bottom of one of my charts. Just one chart on one of my 3 screens - the other two screens are not affected.
However the behaviour is weird.
If I have the chart as half a screen ( top to bottom) - I get the band beyond about 75% height.
If I maximise the screen the band disappears.
Now how weird is that!

sorry but this is way beyond my area of expertise. 99% of the time it's fine and if I ever find a solution/fix I will post.

Actually it was easy....

revised indicator BackGroundGradient3.

Well I still get some odd behaviour but only on the one screen so I am going to assume it's a graphics card thing.