CrossBelow not working on live data

[BigRunningBack]

Hello,
I am seeing a weird problem where my Strategy seems to work fine on past data but when the live ticks come in it suddenly doesn't work. I know I must be doing something fundmentally wrong here...

protected override void OnBarUpdate()
{
if (FirstTickOfBar && Position.MarketPosition == MarketPosition.Flat)
{
if (CrossBelow(RSI(rSIBarLen, rSIMALen), RSI(rSIBarLen, rSIMALen).Avg, 1))
{
Print(Instrument.FullName + " Sell Short!");
DrawArrowDown(Guid.NewGuid().ToString(), true, 0, High[0] + 2*TickSize, Color.Red );
}
}
}

When I first enable this on a live 5 minute chart, all the crossvers "happen". But as the real time ticks come in, the visual chart updates but the crossover never seems to happen as I never see the print or the DrawArrow. However if I disable and re-enable, then the crossovers that didn't occur when live, do get generated once they are history.

Any idea what simple concept I am missin here? I have included Prints as well and the values are fine preceding the CrossBelow() call.

Thanks in advance for any help!

[NinjaTrader_Bertrand]

BigRunningBack, first of all welcome to our forums here - which CalculateOnBarClose setting do you use with this script? False?

[BigRunningBack]

Hi Bertrand and thank you for the welcome!

I have

CalculateOnBarClose = false;

So on the first tick of the new bar if I look back one, it should be the last completed bar.

[NinjaTrader_Bertrand]

BigRunningBack, for realtime runs with COBC = false I suggest running with the lookback increased to 2 to makeup for calling on the currently developing bar. Thus conditions you had for COBC true need to reference one bar further back to express the same.

[BigRunningBack]

Thank you Bertrand, what you said made sense when I thought about it and sure enough it is working now.