First of all....
Use a little program called RegionFrii to set the region of the ISO to whatever you want then use wii brickblocker on the ISO and youīre good to go.
If it still doesnīt work then burn a NTSC disc(not brickblocked) insert the disc answer yes to the question if you would like to update your wiis firmware
(this is how i got metroid prime 3 to work on my pal wii)..
Once it starts updating let the blue meter fill up to about 10%,be careful and donīt let it run to far or your wii will be bricked.
At about 10% pull out the wiis power cord from the wall outlet, let let the wii rest for a few seconds then plug it in.
Now eject the disc and put it it away....
Then burn another copy, use RegionFrii to change the region of the ISO to the one your wii is, use wiiBrickBlocker to stoo the ISO from demanding an update and then burn it.
And now when you insert your newly burned region swapped and brick blocked disc it should work just fine..
Metroid Prime 3 demands that you update from the disc even if you have updated to the latest firmware from another source(internet etc.)
Hope this helps and if you brick your wii or ruin it in any other way donīt blame me, you do this at your own risk, but it worked just fine for me( allthough my pulse was a little higher than normal

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