Maybe there are still bugs on JAPAN version, i test it on US psp slim 9/10 using the old and new chickHEN exploit are ok in entering the ChickHen exploit. But when i try to JAPAN slim, it is 3/10 units that will enter the exploit tiff, and it takes a lot of time and trials. Might also have a problem in the button enter keys which is X for US version ang O for Japan version that recognized the PROGRAM exploit tiff.
:-) still waiting for beta testing. :)