How do I change fonts into another language properly?

First of all, I know this community only on Simpsons game, so even though I'm gonna ask a question about different game Radical Entertainment developed, I feel so sorry I'm asking you guys something out of what the community was made for.

I started making a Korean translation mod for Incredible Hulk: Ultimate Destruction on Gamecube, NTSC ver. I could easily open .rcf and .p3d files thanks to the tools the Donut Team made, and change some png files in p3d into translated ones. It worked just fine. Plus, the subtitles were written in a simple txt files I thought changing the fonts_en.p3d file with Pure3d font creator would end the hard jobs.

Yet, changing the fonts_en file makes the game do nothing when it's opened. It just becomes BLACK. I used <U+10000 option to make Korean font file. Could that be the cause of this problem? I don't know what I should do... It would be very appreciated if you guys give some help. Thanks,,,