I don't know it that can helps you, but I was in the need of a way to add a second layer above the existing base layers, in one shot. That's why I prepared for my vic4's a series of.MC6 files, that I can apply above any other base skin definitions.

As it was Vic4's, i managed to have for each part only one PoserSurface node with a more or less skin-looking diffuse node.

Then, I've prepared the second layer for each part that will use it

Third step: I saved all this in an ".mc6" file

Last step: using a text editor, I modified the file to remove everything that concerns the base layer, keeping only what is for the second layer.

Example:

{

version
    {
    number 12
    build 427
    }
mtlCollection
    {
    material 1_EyeSocket
        {
        materialLayer Layer_1
            {
            name Gloss
            shaderTree
                {
                node "CyclesSurface" "CyclesSurface"
                    {
                    name "CyclesSurface"
                    pos 29 60
                    advancedInputsCollapsed 0
                    nodeInput "Surface"
                        {
                        name "Surface"
                        value 1 1 1
                        parmR NO_PARM
                        parmG NO_PARM
                        parmB NO_PARM
                        node "ccl_MixClosure:Closure"
                        file NO_MAP
                        }
                    nodeInput "Volume"
                        {
                        name "Volume"
                        value 1 1 1
                        parmR NO_PARM
                        parmG NO_PARM
                        parmB NO_PARM
                        node NO_NODE
                        file NO_MAP
                        }
                    nodeInput "Displacement"
                        {
                        name "Displacement"
                        value 0.1 0 1
                        parmR NO_PARM
                        parmG NO_PARM
                        parmB NO_PARM
                        node NO_NODE
                        file NO_MAP
                        }
                    }
                node "ccl_MixClosure" "ccl_MixClosure"
                    {

..........

I don't know if it's by design or by luck, but it works: I can add my second layer above an existing one whenever I want, without changing anything of the base layer. As an ".mc6" file has the name of the different parts, it works. i'm not sure that it would work with an ".mt5" file as it doesn't seem to have any reference for a specific "matLAyer", thus resulting in overwriting the current layer.

Last but not least: this works in Poser 11.3 too

𝒫𝒽𝓎𝓁

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