This indicator is very simple: it shows signals triggered using Fractals and the original ZigZag indicator without any further filtering.
It does never -ever- repaint a past signal and therefore it useful to study the real behavior of the ZigZag -which does repaint- as a trading tool over time.
You should complement signals with your own trading strategy or edit the source code to do it.
As you can see, many signals are repainted by ZigZag indicator over time.
It depends on original MetaQuotes ZigZag indicator -attached-.