I would probably select the light green material which is behind the long beard and hide the rest. Save this texture map with a name. Then Deselect, then Display/Show. Now you can see everything again. Now I would right-click on the light green material and hide it (Select/Dispay/Hide). Now you can save this texture map under a different name. This way you can texture the 2 different areas separately and then load the relevant texture maps for the relevant parts in Poser.