What I did to make it work
Install RM2K_105E.exe
Extract japanese extra files into RPGmakers install folder
Extract VH game somewhere
Run RPG_RT.exe with applocale set to japanese
(this is an alternative to changing your systems language)
http://www.microsoft.com/downloads/details.aspx?FamilyID=8C4E8E0D-45D1-4D9B-B7C0-8430C1AC89AB&displaylang=en
Its important that files retain their japanese names when you extract them and not get renamed to random shit i.e. "É©ëtü@â}âôâRïtù¼.png".
What I did to get them to keep their original names was to run 7-zip with applocale set to japanese.
So yeah, getting this game to work takes some effort...