Responding to Original Poster’s and Sully’s question.
The definitive answer to this question is to look at the code of the indicator: custom-indicators/cumulativeDelta.js at master · tradovate/custom-indicators · GitHub
If “Strong Up Down” is unchecked, the color of the cumulative delta bar is based upon opening and closing price of the current bar. Red if close < open, and Green if close > open. Grey, if close = open. That is, if price’s candle is a perfect doji bar, you’ll see a Grey colored candle for Cumulative Delta.
If “Strong Up Down” is checked, the color of the cumulative delta bar is based upon the current bar’s closing price and the previous bar’s high and low price. Red if close < previous bar’s low, Green if close > previous bar’s high, Grey, if close <= previous high and close >= previous low. That is, current closing price is between the previous bar’s high and low price (inclusive).
It’s very confusing to me. I had assumed the color of the cumulative delta bar was based on the actual delta value. It is possible that the cumulative delta bar will be colored green (because price went up), but the actual delta value is negative.