Hmm I tried to remove and readd Shield Pro but I don't see the new commands
@radioboy @tmm1 I've read this thread with great interest because I too would like to map my Harmony Elite Guide and DVR buttons to the Channels app on my Nvidia Shield TV Pro. I'm on the 30 day trial and I really need to make Channels wife friendly, which will mean correctly mapping the Guide and DVR buttons on the remote. 
@radioboy can I just clarify if you still needed to use Button Mapper to assign the function keys to KEYCODE_DVR and KEYCODE_TV?
EDIT - I found this guide that shows how F1 to F4 that triggers colour buttons, can be mapped to things like Guide and Live TV: https://getchannels.com/docs/apps/remote-control/advanced/#remote-shortcuts
By the way, it seems the "Nvidia" "Shield Pro" device now has the letters "A, B, X, and Y", as well as numbers 0 to 9. I can't see any Function key numbers within either the iPhone or Desktop apps though.
EDIT - It seems the "Nvidia" "Shield TV" model is the profile with Function keys.
@tmm1 which software were you referring to when you asked to try alpha v8.10.2240? If it's the Android TV software, mine seems to be running 8.2.1 on the Nvidia Shield TV Pro.
Hello - I did not need to use Button Mapper for the Function Keys to code the Guide or DVR buttons because I was able to use the built-in functionality of Channels DVR to do that. I did use Button Mapper to map the color buttons, however, to launch apps like Netflix, Hulu and Disney+.
That's a good idea to use it for launching apps - thanks!
Just to tie up the posts in case others find this thread like I did - here is the solution I ended up with: Harmony Hub and Shield - Record Button Mapping?