If Winimage works on Mac, you could do the same step in the first post with an USB drive instead of an SD card. I haven't tried this, but as long as it's a .raw I don't see how it could make any difference.
And it looks like I used a 1GB SD instead of my usual 2GB card when making the first post. Winimage does not create a .raw the size of the content in the device after all. This means that you'll have to use a 2GB or less drive to make the .raw. You can blame Brawl for not supporting SDs larger than 2GB.
And it looks like I used a 1GB SD instead of my usual 2GB card when making the first post. Winimage does not create a .raw the size of the content in the device after all. This means that you'll have to use a 2GB or less drive to make the .raw. You can blame Brawl for not supporting SDs larger than 2GB.