I also found the correct way to get the last breakout fractal:

var FracalUP = FractalHigh(series(priceHigh()),5);
var FractalDW = FractalLow(series(priceLow()),5);

To access fractals back history:

vars FractalUP = series(FractalHigh(series(priceHigh()),5));
vars FractalDW = series(FractalLow(series(priceLow()),5));

and then FractalUP[n] and FractalDW[n]

Ok, I am trying to test my strategy with zorro but it is not too easy.
Thare are a lot of settings to be considered: TICKS, PARAMETERS, FACTORS, NumWFOCycles, NumBarCycles, NumOptCycles, LookBack and so on; even slightly changing these values ​​the results are completely different.

Have you a template from which to run a reliable back test?

TICKS only needs to be used if you are entering with trade management functions. PARAMETERS is required if you have optimised variables in your script. FACTORS is used when calculating optimal margin. Most backtests should use NumWFOCycles anywhere from 6-12 and NumBarCycles can help generate more trades if not many signals are generated with your strategy for more reliable results. LookBack is needed in most cases especially when using indicators, and should be set at double your longest timeperiod used to generate your indicators. I dont believe there really can be a template cause which Modes to set depends on the script and strategy you are using.

The best way to learn trade system development is learning by doing. Knowing many indicators is not very important, but knowing how to test a system is important. System development is empirical, so testing is everything.

First try to understand what the parameters are doing, from their description in the manual. Some of them are for special cases only, but most - especially those that are also used in the tutorials - are essential for properly testing a system. You'll find them, under different names, in any serious automated trade software.

If you are not sure what a certain parameters does and how it affects the system, experiment with it and check the performance sheet. If then there are still open questions, ask them here.

Just a question for now.

If I utilize a stop in my script, I must use the TICKS for testing? Otherwise zorro check the stoploss only on every bar close, right?

Not necessarily. Even without TICKS the stops are realistic, they use an intra-bar price curve approximation.

TICKS is more precise however, and is recommended when the trades are very short, f.i when many trades open and close within the same bar. TICKS should also be used when you use a tick based function for trade exit.

I made a ever-increasing profit curve with no-tick based test but when I test it with a tick mode the strategy quick-changed to a loss strategy.

What is a character of those strategy?
in both test modes, The strategy needs to be profitable to ensure robustness?

No, the TICKS result always overrides the result without TICKS. So that strategy was indeed losing and the profit was possibly an artifact of inaccurate entry/stop approximations.

A robust strategy must show profits under all normal circumstances and test modes. It happens frequently that a test generates profit, but loses when you change some parameter a little. Such a system is not profitable.

Can I read the current market price (Ask & Bid) with zorro?

var Ask = priceClose();
var Bid = Ask-Spread;

http://manual.zorro-trader.com/price.htm