Quick release chain/gate latch -OpenScad CSV

I asked my fitter to make quick release latch for our rescue boat safety lines
based on nice Auto Gate Latch by peaberry https://www.thingiverse.com/thing:2998264
When I saw his make, well ... I was forced to make own design to show him how it should work.
Here is a result (code included) with and without securing pin.
It is intended to make from steel plate 4mm thick, dim.50x50mm, but for home use with low force PLA printout should be OK.
If You want to make some changes, read code

Enjoy!