G'MIC in NATRON (Help with layers ...)

Specifically i’d like to know How to use G’MIC filters with 2 image inputs in Natron.

For example I don’t understand how “layers” G’MIC concept is translated in NATRON that uses “channels”.
My goal is to create a grid warp for NATRON

I’m already a commiter to NATRON documentation, so any link to G’MICs filters documentation is welcome

The docs are here:
https://gmic.eu/reference.shtml
https://raw.githubusercontent.com/dtschump/gmic/master/src/gmic_stdlib.gmic
gmic-community/template.gmic at master · dtschump/gmic-community · GitHub

I haven’t delved into Natron yet. In G’MIC channels are spectrum channels (e.g. red) and layers are images (e.g. image_name[index]).

If you are using the GUI plugin, there is a selection menu for inputs. You can select the following:

Screenshot from plugin launched from GIMP.
image

Your right now I see many parameters (in a GMIC Effect in NATRON) named “layer” that can determine what is actually passed to gmic

gmic_layers_screenshot01

Thanks