MedianRenko cBot..

I have a problem to understand an idea of how the Renko color change works. I need to program a cBot with the MedianRenko.calgo indicator. Could you please help me and give me some code example how to place a pending order BUY when the color is Green and SELL when it is RED ? I will very appreciate your help. Thank you. 

//-----------------------------------------------------------------------------------------

private MedianRenko _renko;

protected void OnStart()

{

  _renko = Indicators.GetIndicator<MedianRenko>();

}

protected void OnTick()

{

if (_renko.color[OneBarAgo] == "Green")

PlaceStopOrder(TradeType.Buy, Symbol, VolumeInUnits, Symbol.Ask, "BuyStopOrder", StopLoss, TakeProfit, null, "BuyStopOrder..");

else if (_renko.color[OneBarAgo] == "Red")

PlaceStopOrder(TradeType.Sell, Symbol, VolumeInUnits, Symbol.Bid, "SellStopOrder", StopLoss, TakeProfit, null, "SellStopOrder..");

}