There isn't much to explain, I asked help on this a LOOOOONG time ago (how to use the pspiofilemgr with vlf) but nobody helped (or everybody ignored my question).
So today I decided to pick up where I left off my ASIV for VLF, and created a working version of the pspiofilemgr for the Vlf.
You'll have to load the prx from crt0.c and use the given stub and header files.
Anyway, hope this comes in handy (download's attached). Enjoy!!