Hi, @Thebroughfamily,
My bad, I think I did a poor job explaining myself. The USB3-to-Ethernet UE300 I bought works... but in another thread it was found that rtl8152 drivers in Linux fail due to autosuspend issues: Update kmod-usb-net-rtl8152 Driver to avoid USB 3.0 to Gigabit LAN issues?
Because, sadly "down unda", we do not have proper broadband bandwidth at our disposal —how I miss my cheap symmetric 600/600 Mbps from Spain— it does not matter to me that asix-ax88179 drivers are not so efficient, as long as they are stable and without the rtl8152 issues, which seems to be the case. This is the only reason I am waiting on an upgraded driver for rtl8152 in Linux/OpenWrt. And, this is the cheap adapter with ax88179 chipset I bought: https://www.amazon.com.au/gp/product/B00MYTSN18/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
In regard to creating an image with Image Builder, my steps are only in case you have already OpenWrt installed in your device, please, be aware of it as otherwise, makes no sense. What part do you find tricky? I know I tend to be oblivious to detail as I think most people will manage, apologies again if it is not the case, mate.
Kind regards.