I am getting the same issue. I find that if I let the video settings display NTSC it works (although with a fucked up image). As soon as I try to force the video to PAL is when the black screen happens.
How do I fix this?
I honestly think it's still a settings issue. I've have a PAL Wii and have plenty of games that are NTSC. I've often had Black and White issue and resolved them simply by forcing the proper PAL format via USB Loader GX.
Start USB Loader.
Click on the game you want to play.
While on the disk screen, select Settings.
In the settings menu there is an option for 002 error, turn this on.
This should resolve your problem.