I'm on Wii 3.2E and using Backup Channel to load.
I downloaded SSBB.
First I tried burning it with a TDK DVD+R DL using layerbreak. I got DVD read error 324. Then I tried Verbatim DVD-R DL ( layerbreak not possible ). The game loaded but froze were early ( just when you had to choose whether to use a memory card or not ). I then tried Verbatim DVD+R DL using layerbreak as suggested in the download instructions for this game but then I simply got a DVD read error like with the TDK.
if it's any consolation i have never got a dual layer anything to work! film/data/game they all fail....try and find the dvd5 version of it - though it could be that your cios/loader don't support dual layer, make sure you have the latest of both ie neogamma r6 and cios38 r13