I know this isn't directly a Japanese freebie for Poser users, but for folks still using Daz Studio 3.1, Tofu-San has made a plug-in script for LuxRender export, which doesn't need Reality. 

http://tofusan.cocolog-nifty.com/blog/download.html

Scroll down the list of his safe-for-work freebies and you will see the item towards the bottom.  (Note: his next page is for mature items only.)

Eternal Hobbyist