Hey,
I have been trying to get Ninja Gaiden Black work on my jtag xbox360. It wouldn't even work with my purchased copy of the game! It is always freezing at the 'xbox' screen after launching the game. No matter whether the game is launched in the xbox dashboard, or from Xexmenu on the 'default.xbe'.
So I tried everything mentioned in this thread, formatted my hddx again and again, copied the 'Compatibility' folder, still no luck. I even downloaded a copy of the game somewhere else and put it on my usb drive, but it was still the same!
48 hours have passed since I started trying so would really appreciate some help. By the way my NGB CD did work before I jtag my console, but now I always get a freezing 'xbox' screen.