First, re-load whatever skin shader setup you had already, because it looks like you have changed some stuff that maybe you'll end up wanting plugged in again.

Unpack that zip file containing the lip mask somewhere you can find it.  RuntimeTexturesDAZCharactersMilWomV4 is where the basic V4 textures are stored, maybe you could put it there - anywhere you know where to look for it, it doesn't matter that much.

Next, look at the PoserSurface root node (the big thing on the left that everything plugs into).
Find Alt_Specular, near the bottom.

Find what is plugged into it, don't unplug anything yet.  Drag that node away from the others so you can keep track of it.  Now that you have it away from the others, go ahead and unplug it from Alt_Specular.

Look at the highlighted stuff.  Those three nodes are things you have to add.
1 Blender node (Math -> Blender)
1 Glossy node (Lighting -> Specular -> Glossy)
1 Image Map node (2D Textures -> Image Map)

In the Image_Map node, click the first line Image_Source and drill for that map you extracted from the zip file earlier.

Plug your Blender node into Alt_Specular on the PoserSurface root node.
Plug whatever you disconnected in the first steps (whatever was originally plugged into Alt_Specular) into the first plug of your Blender node.
Plug your Glossy node into the second plug of your Blender node.
Plug your Image_Map node into the third plug of your Blender node.
Click the number value of the third line in your Blender node and make its value 0.5 (different values can work too, play around with it, you can see in that pic I have it set to 0.5).

Done.

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