I finally compiled and installed LEDE (snapshot r6577-da95c9a, kernel 4.9.73) on the above referenced router. I'm performing initial checkout of functions, and noticed the LEDs are not showing the proper status for some items. The Power and WAN LEDs are correct. The LAN, USB and WPS LEDs are always ON -- should toggle. The 2.4G and 5G LEDs are always OFF -- should toggle as well. They work properly with the default Hootoo's MediaTek version of OpenWrt.
Has anyone run across LED issues with other mt7621 based routers? I will keep working on the .dts, diag.sh and 01_leds files and keep searching the forums and internet for additional info.
Thanks for any help you can provide.