Wait, your trying to burn .sbi files with discjuggler? can you do that?
also, there is no gba emulator for DC that can play commercial roms. You may have downloaded the one that can do homebrew, and im fairly sure the sbi file of that will only play the included h/b roms. Making that new folder may be the problem.
I think the problem is how your burning it, use SelfbootInducer, extract the file then burn using the selfbootinducer aswell, you cant really go wrong as there is a tutorial included with selfbootinducer. You can download selfbootinducer's set up file (Sbindv4.exe) here as well as various .sbi files.
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