Hi,
I assume that you're referring to the current bar being under construction for the indicator AC. If so, it is indeed moving along with the current candle til it's completed and new one is formed but I never noticed/seen red and green bars on both ways of the zero for the AC or Awesome indicators neither in Jforex platform nor in Visual Jforex Historical tester.
Once the new candle is created, the AC bar will start wih a given colors and then gets updated and may turn to the other side of the zero. It is the same in VJF, the only particularity is that once it changes its color the previous value will remain saved at the level of the variable.
Hope this clear enough
Don't hesitate to attach a screenshot for more details
Thanks