I installed firmware openwrt-ar300m-nand-clean-2.264.tar on my AR300M and I lost the GLI GUI I only have access to LUCI. Does anyone know how I can install the GLI GUI again? I like using LUCI but it doesn’t allow me to import my OVPN files the same way as the GLI GUI does.

The clean version is just that -clean OpenWrt.

The full GLi firmware is what you want if you need the GLi ui.