"I am not sure exactly what was done but I think there was a blue colour added to the ambient which has to be removed from older sets if SSS is used."

Nope.  You're thinking about the blue diffuse chip to counter balance the deep red expressed be the ambient_color chip.  Laurie has it right, BB's VSS Prop native skin shader contains the node arrangement necessary to fake SSS.  

Thanks for putting me right, at my age my memory is not what it used to be.  At least I got the colour right.

 

 

I use Poser 13 on Windows 11 - For Scene set up I use a Geekcom A5 -  Ryzen 9 5900HX, with 64 gig ram and 3 TB  storage, mini PC with final rendering done on normal sized desktop using an AMD Ryzen Threadipper 1950X CPU, Corsair Hydro H100i CPU cooler, 3XS EVGA GTX 1080i SC with 11g Ram, 4 X 16gig Corsair DDR4 Ram and a Corsair RM 100 PSU .   The desktop is in a remote location with rendering done via Queue Manager which gives me a clearer desktop and quieter computer room.