i am trying to create a scan for bulkowski vertical run down 

1. their are at least 4 price bars vertical down with little overlap

The following allows a bar to have up to 25% of its range overlapping the previous bar. It does not have a limit on the size of the bars.

TrueInRow(C < O AND C < C1 AND 3 * H + L <= 4 * L1, 4)

The formula does not require any sort of minimum bar size or that the body be at least a certain percentage of the candle.

is their a post to explain true in row this is not a pcf formula is that correct 

That is an actual formula. You need to be using TC2000 v17 or the TC2000 v18 beta in order for it to work however.

If you are using an earlier version of TC2000, you would need to check for each bar individually.

C < O AND C < C1 AND 3 * H + L <= 4 * L1 AND C1 < O1 AND C1 < C2 AND 3 * H1 + L1 <= 4 * L2 AND C2 < O2 AND C2 < C3 AND 3 * H2 + L2 <= 4 * L3 AND C3 < O3 AND C3 < C4 AND 3 * H3 + L2 <= 4 * L4

i am running version 12.5 on my mac, i put the formula in and got no scan results today 

The base formula is currently only true in a row for 2 bars at most versus the US Common Stocks WatchList in a daily time frame.

The following symbols in the US Common Stocks WatchList have met the requirements at least once during the most recent 100 bars in a daily time frame.

AGI, BELFA, CFBI, CHCO, CNET, HAIN, LENS, MPB, RIOT, TAYD, TCI, & YERR