@Rhia, here's what I get when I use GoPhysical on the Sofa_1 material for the sofa.

Same issue with the sofa textures. The Color map was originally connected to bump, so that may be whyGoPhysical didn't create a roughness map. The Roughness setting in the Physical Surface is set to 1 (which is very "flat"). Adjust to somewhere between .5 and .8 depending on how satiny you want it to look. Then click the Specular color chip in the Physical Surface node and "pick up" the Specular Color from the PoserSurface node. Those are the same changes I made for the wall.

To be clear, I don't think the problem is with GoPhysical, I think it's that the original materials don't have much to "convert" from. Can you take a similar screen shot for what you get for the sofa material when you have a chance?  I am curious to see if the preview chips look similar or if you are actually seeing a black preview in there.

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