I have a wii in CPH and in Almería. And I keep forgetting how to add games. So this is the final list:

1. The folder structure of the SD is placed on the owncloud, and it should be fat32
2. Download the roms from here
3. The format is rvz, but you need to add it as ISO. To do that you need to download dolphin
4. In dolphin go to preferences and add the folder of your ROM.
5. When is listed in the games, right click and convert. You will generate the ISO file
6. Then on Wii Backup Manager, you need to add the drive, and then add the games. And then transfer
7. Dont forget that in the wii you need to update cache