Hi Helper,
Using your explanations from previous post, I did a custom VI to do the job. Find attached library and let me know if it's working properly.
Regarding the way you refresh the picture, it depends on content (for example, if the background of an arrow is always the same color you can delete that, drawing another one in the same position using background color - this way you can refresh the picture without drawing everything else again).
Anyway, probably a good idea will be to start with a picture containing everything "static" in order to redraw just "dynamic" elements.
Hope this helps.