And again with the mosfet symbol

 

Thanks for the files. I will check the schematic against my power supply and change component references/values where needed. I would love to be able to run a simulation but then i need to find spice info on the transformers (doubtful).
My goal is to add constant current mode without having to modify the power supply itself. No fancy stuff with a microcontroller, pure analog using a ACS712 hall-effect current sensor and analog conditioning to set the output voltage. And a second option, disable the output when a chosen current is exceeded - reset with a pushbutton (as in my very old power supply).
I know these power supplies are also available with a variable current limiting option. We can even modify the ones without by adding/changing a few components at the TL494 but, as i mentioned, i don't want to modify the power supply.
Such a circuit (if it works) should be usable with other (non digitally controlled) power supplies.

 

Here is the kicad schematic file. I'd be interested in hearing about your modifications.

There is one error in you Kicad schematic: The wire going down from T2-6 shouldn't connect to the cathode of D5.

Starting from your schematic, i created the schematic of my power supply (Kicad file attached).
There are a few differences:
Power mosfet gate circuit
auxiliary power GND wiring (DK912)

Next test: ACS712 constant current mod.