Openwrt based vendor firmware

I am currently trying to change the i18n files on a chinese router called newifi3 d2 on its stock firmware.
the stock firmware is based of pandorabox OpenWrt BARRIER BREAKER

so ive extracted the stock firmware using firmware-mod-kit and made the changes, the problem comes in after flashing the rebuilt firmware, it woont boot, i have no problems whatsoever on using fmk on any openwrt firmware but this is the first time ive encountered this problem.

tried to find leads over the internet but i cant find any.
this is my last resort.