To confirm, then for no visibility Animation[0].0 = 0 and for visible Animation[0].0 = 1?
yes, when Animation[0] = 0 (bit 0 off) it will show the line as state 0, which you configure as "Not Visible", or transparent.
and when Animation[0] = 1 (bit 0 on) it will show the line as state 1, which you configure as "Visible", in your chosen colour.
The "Indirect Window" object is a pain to use. It has to be top-most layer, so that it obscures what it is supposed to cover, so that's where you put it. But if you do any screen editing in that area, new objects automatically become top-layer. You have to keep remembering to promote indirect windows back to the top-layer, or they dont cover what you want covering !! I have suggested they make them "sticky" so that they can't get demoted once put as top-layer.