This seems very weird to me, because the Kozuka fonts are the only ones that cannot be used.
My system: Windows 8 64-bit, MikTeX 2.9 64-bit, TeXWorks 0.4.4 r.1003.
\documentclass[12pt]{article}
\usepackage{fontspec}
\defaultfontfeatures{Ligatures=TeX}
\setmainfont{Meiryo}
\begin{document}
Hello, world! わたしはにんげんです。
\end{document}
works and produces the expected output: Text containing Latin and Japanese characters.
Using \setmainfont{Arial} instead of \setmainfont{Meiryo} also produces the expected output: Latin characters and squares instead of Japanese characters because Arial doesn't contain those characters.
Using \setmainfont{alkjsfd} also produces the expected output: fontspec error: "font-not-found".
But using \setmainfont{Kozuka Gothic Pro R} produces just an empty sheet of paper.
I have no idea why.
