Asus RT-ACRH17 Openwrt installation process

[Rakesh344]

how to install openwrt on Asus RT-ACRH17 router????

[frollic]

Need help installing OpenWrt on asus RT-ACRH17 REV 1.60 aka RT-AC42U

need help installing OpenWrt for the first time on an asus RT-ACRH17 REV 1.60 router that still has the factory firmware installed. This hardware is listed as supported and the same hardware as the RT-AC42U model router. I tried to install using the stock firmware upgrade method from the webGUI but the openwrt file was rejected as a bad firmware file (I suspect it's signature may not have matched or somesuch. ) I moved on from there and have now most likely voided the asus factory warranty by…