1.  Not really.  There's 3 different conversion options in SkinVue - Enhanced, procedural and one I never use and can't remember the name of.  The Enhanced conversion uses the original texture maps for the figure but adds a whole lot of other nodes and stuff (the function editor for a SkinVue material looks a bit like an explosion in a wool factory - lines everywhere :) )
You can use the "Render with Poser Shader tree" option if you have a lot of RAM - I still think SkinVue looks better though (and does a much better job of SSS and Fresnel than would otherwise be the case)

2.  You can use SkinVue on any texture you want.  It doesn't replace the maps but it enhances them a lot.

Hope that helps

Regards

Frank

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