OpenWrt installation on AirLive traveller 3g II

Greetings to Experts here

I'm trying to flash OLD AirLive Traveller 3G II to be able to use bridge by relayd.
some captured menu attached
searching for step by step installation guide with no luck.
but i got this link

I hope masters here would help me to solve my problem,

please comment
thanks a lot.

My guess is that you flash directly the OpenWrt firmware.

I can't. it says "wrong file" as it begin to try to read the OpenWrt file.

Try to shorten the filename to something that is closer to the original firmware name.