Hi! I've definitely done that and everything else works perfectly, I've followed guides on YouTube too and triple checked that the main and backup that I've edited are exported back (into the SD card). I've seen a few people have the same problem too even when following everything but haven't seen any solutions that have worked for them yet. I think I'll just keep trying since I've heard from a few forums it's just not completely reliable yet. Thank you though! :-)
For people having people with PkHex. I recommend outright deleting the backup, seriously. I tried editing both files so everything would be the same and it just didn't workout, some changes I made stick, but others didn't, so I tried deleting the backup and ever since then everything has been working smoothly. So yeah, get rid of the backup and work only with the main.