I think there is a problem in Z12+ and Z6+ regarding the time zone.
These strategies "live" in EST / Eastern Standard Time (New York) as it seems which is UTC-5.
Because of that the market closed trigger is active too late on Friday/Saturday and the market open trigger on Sunday/Monday is also too late when trading in Europe.
This leads to duplicated/multiplied price quotes before the weekend mode and missing prices and too late continuing trading after the weekend.

Here is an example of a Z12+ run:

Lookback in the log file:
[1870: Fri 26-02-27 13:00] (1.36290)
[1871: Fri 26-02-27 14:00] (1.36316)
[1872: Fri 26-02-27 15:00] (1.36395)
[1873: Fri 26-02-27 16:00] (1.36369)
[1874: Fri 26-02-27 17:00] (1.36369) <-- same price as before!
[1875: Fri 26-02-27 18:00] (1.36369) <-- same price as before!
[1876: Fri 26-02-27 19:00] (1.36369) <-- same price as before!
[1877: Sun 26-03-01 23:00] (1.36487)
[1878: Mon 26-03-02 00:00] (1.36584)

Trading:
[Fri 26-03-13 15:00] 9914 0 0/2 (1.37292)
[Fri 26-03-13 16:00] 9935 0 0/2 (1.37180)
[Fri 26-03-13 17:00] 9935 0 0/2 (1.37195)
[Fri 26-03-13 18:00] 9935 0 0/2 (1.37195)
[Fri 26-03-13 19:00] 9935 0 0/2 (1.37195)
Market closed on 03-14 01:00:03 (local 20:00) <-- local 20:00 is wrong! It probably was 2:00 in Germany on Saturday
Market open on 03-16 04:00:07 (local 23:00) <-- local 23:00 is wrong! It probably was 5:00 in Germany on Monday
[Fri 26-03-13 20:00] 9813 0 0/2 (1.37127)

In an additional test with Z12+ (started with EUR/USD set in Zorro) I checked the actual prices to be able to match the real German time. The lookback looked like this:
[4124: Fri 26-03-27 14:00] (1.15167)
[4125: Fri 26-03-27 15:00] (1.15062) <-- Friday 21:00 in Germany (close price 21:59)
[4126: Fri 26-03-27 16:00] (1.15062)
[4127: Fri 26-03-27 17:00] (1.15062)
[4128: Fri 26-03-27 18:00] (1.15062)
[4129: Fri 26-03-27 19:00] (1.15062)
[4130: Sun 26-03-29 23:00] (1.15153) <-- Monday 5:00 in Germany (close price 5:59)
[4131: Mon 26-03-30 00:00] (1.15133)
[4132: Mon 26-03-30 01:00] (1.15154)
[4133: Mon 26-03-30 02:00] (1.15125)
End of lookback period at 07:25:30
--> Friday 15:00 price is there multiple times, but Sunday 23:00 to Monday 5:00 prices are missing

The same applies to Z6+.
Z7 on the other hand is not affected.
Maybe it is a problem with the C++-based strategies?

I tested with MT4 bridge on a demo account if that matters.

Forex strategies dont live in New York or german time. Forex is traded 24 hours, weekend is Fri 20:00 - Sun 23:00 UTC unless you set up something different.

Sure, but I didn‘t configure anything regarding weekend.
For Z7 the weekend period is determined as it should be while Z6+ and Z12+ go to weekend mode in New York time — not UTC time.
(and they print the New York time in the log as local time)
This is 100% reproducible here.

But your log is utc. No new york. The displayed time is your PC time converted to utc. If it is wrong then the clock or time zone on the PC is set wrong?

It is running on the same PC where Z7 shows the correct UTC time.
I just checked again.
For the current hour (23:.. in Germany) Z7 shows:
[Wed 26-04-01 21:07]
On the other hand Z6+ and Z12+ show this:
[Wed 26-04-01 16:00]
So this is UTC-5.

My Z6+ shows 21:28. I dont think C++ has a different time than C so the reason is probably something else, otherwise other people had also a wrong time. Maybe you should contact the support and send them the log.