Aren't you still supposed to format before downgrading? (I haven't done one since before the CTRTransfer became a thing but I used the OG DSiWare method when you had to patch the NATIVE_FIRM on the PC) Just a guess but I've seen a lot of frankenfirms/soft bricks because people fail to format before/after the process. Pretty sure it's necessary to make sure you're working with a clean SD and clean NAND to avoid incompatibilities. You can totally soft-brick from having an SD card with bad sectors, or an edited HomeMenu etc etc.
Interesting both of my successful installs were on brand new devices, so they were as if they were just formatted... Hmmm, aren't those bricks caused in downgrade tho?







