Everything that had pokethrough gets fixed with setting "match end points" after conforming the item.  The only clothing item that retains pokethrough is the Jack of Hearts shirt - funnily enough the one I started with and wanted to render.    I can always conform it in P7 and then reopen the .pz3 in PP2012 though.   If anyone has that shirt and cares to try it out I'd really like to know if it's just me or if it's you too :)