The same goes for me. I tried to change the names of the characters (names.dat JAP 16 kb, USA 12 kb) via HEX editor. First I looked for the very start and ending points in START.bin with the JAP names.bin as guide. Found the places, cut them out und replace it with the code from USA name.bin. I got a flashing white Screen after the "NIS America" logo. I think working with the editor is a dead end.
We should ask the guy for help who made the NISUnpack.jar. Maybe he has the right tools to repack .dat files (if he can decompress und decrypt those files he should be able to put them back together).
If it's possible, keep us informed about what you're doing - I can jump in and help
Oh, I can say - I conquered black screen so far:
1) Grab Japanese version as a base - BJLS10095
2) Replace START.DAT (BJLS10095\PS3_GAME\USRDIR\data\START.DAT) with an US equivalent one (BLUS30727)
3) Game starts, reminds about update (ignore it, as it's 3.60), - game goes to loading screen, few minutes it loads something (external HDD blinks), after a few moments HDD stops to blink, but the "Loading..."
screen continues infinitely
It's the closest I could get, trying diffirent variations.
.DAT files can be unpacked via NISUnpacker, and further decrypted with NISDecomp.
Good luck, I'll try to play with asia version too.
How do you make the game start-able ? When I want to start the ASiA (edited PARAM.SFO) version, I got an error message and it quits the game.