you dont even hav to bak it up...u should b able to play the japanese game without any problem with ur swap magic but even if u do back it up it should work
yes thats the magic of swap magic. actually the only way i could play a pal game on my usa ps2 was to copy it to my computer and convert it to ntsc. i bought pilot down behind enemy lines pal vers. did ALOT of reading and converted it, now it works fine. before the game freaked out when trying to play cause pal on usa tv's wont work.