Default Allwinner A31 4.2.2 ROM amendment help

I hope I got the right place to post.

I have a Measy U4K miniPC stick that came with an Android 4.1.1 ROM. Measy did not make this ROM public, nor have they provided the promised 4.2.2 update.

However, the TV Box CS918S has had multiple releases of 4.2.2 ROMs and has the very similar architecture. I can flash the ROM but wifiand SD card don't work. After a lot of investigation and meddling I have traced this to the Wifi Power pin being different, the CS918S uses dld01 whilst the U4K uses aldo1.

I have used both Windows and Ubuntu based kitchens to try to amend the ROM to work on the U4K but with no joy. The key files that controlled config in the 4.1.1 builds such as sys_config.fex, bootloader.fex and script.bin seem no longer to matter. In fact, script.bin no longer exists.

From what I can see u-boot.fex has the config compiled in. I've tried hex modding to change dldo1 to aldo1 but then the image won't flash, presumably due to CRC error.

Can anyone help me out with this?

For ref the latest firmware can be downloaded from [link deleted as I do not have privilige yet]