make sure bannerbomb is the only thing in your private folder (if u have other personal channels or game saves it may prevent bannerbomb from launching correctly)
BB should be working though, so I hope we can get to the bottom of this, but if it still gives u problems, u may want to consider the indiana pwns hack, it would mean u need to spend 5 euro or w/e to rent the game, but a small price to pay.
The sd-card reader had a problem.
After serveral times pushing the sd-card in and out suddenly i had connection with the sd-card.
I have test it with a photo on a other wii and there was no problem watching this photo.
After this test i was sure the problem was in the sd-card reader.
THANX a lot for the support.