I'm not sure, some people reported problems because the different video systems,
@Sumea did a quick tutorial about how to patch it.
Edit: It seems TeconMoon can patch it on the fly, from the OP:
Advanced settings
As cucholix mentioned,
@Sumea managed to figured out why Wii games boots to black screen, reason being is the video modes that has been encoded into the Wii game.
Here is the run down:
What Works:
USA Region Console: USA region games works fine.
EUR/PAL Region Console: EUR/PAL region games work fine.
May/May Not Work :
USA Region Console: EUR/PAL region games, most will boot to black screen.
EUR/PAL Region Console: USA region games, 50/50 chance the game will work.
Now moving along to Video Mode Patching.
NTSC to PAL: Has a
HIGH success rate of games working on EUR/PAL region console with this patch.
PAL to NTSC: Very
LOW success rate, or not work at all.
So it's best practice to inject
YOUR region games if you want a working inject or you'll get the dreaded boot to black screen.
As for those exclusive EUR/PAL games that is not released in USA, only way to find out if the game will work on USA region console is to inject as per normal, hoping the game will boot, if not, then re inject with the PAL to NTSC video mode patch, and see if it works, if it doesn't, then your out of luck.
Reason why games that do work on cross region consoles is probably due to the game developer encoding the game video modes to cater for both NTSC and PAL.
Such apps like
Generic Wii Patcher and
Wii VMC which checks the MAIN.DOL file for video modes, you will see each game will have varying video modes for that game, this is possibly due to the various video formats around the world, as the Wii only had
Composite Video (Video: Yellow, Audio: Red/White) and
Component Video (Video Red/Green/Blue, Audio: Red/White) and I believe there is
SCART cable was in the mix as well. So devs had to encode the standard video modes for that region in there games. It would have been nice if they included ALL video modes in their games. These days we don't have this issues as HDMI is pretty much standard.
The above info is from personal experience with injecting, mainly for others, when starting Wii injects in the beginning, I had a few feed backs regarding PAL to NTSC injects, and all the injects I did, didn't work, all boot to black screen.
Hope this info helps.