Did you put the updated files in the appropriate places? I wasn't sure if this helped but I deleted the config.bin in /luma/, I booted directly to the config menu after, went through that, shut down the console, boot holding start to launch the chainloader and update B9S.
=> start_SafeB9SInstaller.firm in the payload folder.
=> boot9strap.firm + .sha in the boot9strap folder yes.
Gonna try deleting the config. Thanks o/