I developed many indicator and strategies for NinjaTrader.
I will develop indicator with values 4 green dot, all instruments closing up, value 3, 3 instruments are closing up, 1 down, value -3 3 instruments are closing down and 1 instrument is closing up and value -4 all instruments are closing down.
Indicator is calculate on every tick (CalculateOnBarClose = false) because with renko bar type close of bar for instruments are not at same time