I'm dealing with the v5 hardware release of the router above and compiled from scratch the openwrt at r16769 .
Usually I used to pre init the network config with the old chaos calmer release (used for the v2 hardware release) and usually I put a preconfigured network config file with static content in the files directory of the build. This because even if I preconfigure it in the make menuconfig (look at the attachment) it do not keep the IP address put after the boot finish. Usually it take that address only for the preliminary boot phase and for the failsafe config but later it switch to its default IP 192.168.1.1. I usually solve the issue with the preconfigured static network file in the build dir.
But with the v5 hardware is saw that the network file the router generate at first boot have a dynamic part that is :
config device 'wan_eth0_2_dev'
option name 'eth0.2'
option macaddr 'cc:32:e5:84:92:de'
That is dynamically created ad first boot based on the device hardware.
Now, if this section is important for the device I cannot anymore manage the network file in a static way that is equal for all devices that I flash.
The best should be to maintain the configs that are inside the make menuconfig (pre init parameters) but I cannot t find how to do it.