AMI BIOS Aptio V - Linx 12V64 UEFI BIOS Help

[IAmOrion]

Quick back story... I'm new to bios modding and having some issues with my old Linx 12V64.  Originally I was trying to revive this old tablet and during my internet travels came across AMI Bios' ChangeLogo tool.  I changed the Logo but managed to mess up the flash and ended up with a paperweight for a day.  I got myself a CH341A and managed to rescue it, but now I'm trying to understand WHY things don't work.  If I change even 1 BIOS string using the AMI BCP tool it turns into a paperweight again. (I obv have a backup hence able to recover it)... but from some testing it would appear that no matter how simple the change, ANY change renders it useless despite flashing correctly and using "official" tools. 

What am I missing? is this normal? Is it something to do with the Signature Verification stuff? (I got a warning about signature verification in the changelogo application, although AMI BCP does *not* give that same warning.)

Edit: I used FreeDOS Live when I flashed, also the EFI version from an EFI Shell, never flashed from windows. I obv used a second computer when using the CH341A to recover