I am having problem installing ROM Hacked CIA on one of my 3ds. The game is Pokemon Alpha Sapphire installed with cosmetic mods. I have tried installing this modded ROM onto my "regular" 3ds SysNAND 11.1 using FBI, but was not successful as it showed invalid checksum after reaching almost full installation. So I tried installing the same CIA file on my "backup" 3ds, which the only hardware difference is the size of SD card and software difference is that it has nothing significant installed (FBI and DevMenu, pretty much thats it). Initially it gave me same result on FBI but when I changed over to DevMenu for installation, it worked.
Knowing this, I retried on my "regular" 3ds again with DevMenu, but it failed again. Re-downloaded the CIA, but result is unchanged. As a just-in-case verification, I have tried installing my CIA, which is ripped straight from my physical cartridge. This has installed no problem, even in the FBI, and I assume that there is no hardware/software problem (at least on surface) for CIA installation.
I hope that someone can help me out figuring out what is causing the issue for failed ROM Hacked CIA file, and the method to solve the issue.
The only thing I have not done, from what I can think of, is system reset through 3ds settings and install everything again after formatting my sd card. However, I would like to leave this as a last measure.
Below are the details for 3ds'es
"Regular"
Model: New 3ds XL
Region: US
Hack/Mod: A9HL + Latest Luma
NAND/Firm: SysNAND 11.1
Game/Software: Many installed
SD Card Capacity: 128GB
"Backup" (mostly same with "regulr")
Model: New 3ds XL
Region: US
Hack/Mod: A9HL + Previous Luma (I think one version lower than current, 6.5.2?)
NAND/Firm: SysNAND 11.1
Game/Software: Barely anything installed
SD Card Capacity: 32GB