First off, you're doing it wrong. You need mgba.3dsx, not .cia. Second off, mgba.3dsx and mgba.smdh are supposed to go in a folder called 'mgba'. That folder should be placed inside the '3ds' folder.I need some help.
I downloaded the latest build and extract it, it says error, and this happens:
Anyways, I put it in the SD Card, but it doesn't work.
Not to mention all your files are 0KB, which essentially means they're empty. Try redownloading them, or check your SD card to make sure it's not messed up.