I don't have GR6, they're not getting any more of my money until they have enough new amps (the old one's mostly suck IMO), and if they've diminished their once best in class MIDI implementation, I may never upgrade. I'm currently struggling in GR5 to get the Looper working. No problem in Helix and THU. I'm waiting to hear from NI Support on why the Looper doesn't properly respond to MIDI.
OK, I DL'd the GR6 manual. It looks like they've changed how you view things, but the added ability to save an effect's MIDI settings as GLOBAL for that effect actually seems like an improvement. The main change seems to be that the CONTROLLERS screen is gone, so you need to right-click on each parameter, then use LEARN, choose whether you want to save the settings as GLOBAL for the effect, then save the preset. Assuming that this means you can re-use CCs, it's an improvement.
The configuration I've posted to EJ's UNO2 allows for 9 controllers in the DIRECT bank. Everything should work as in GR5, and using UNO2 vs UNO, you have 9 controllers vs 5 in UNO, and access to the full 128 presets in each bank. It's unclear from the GR5/GR6 manuals if there's a way to do Bank Changes via MIDI. I couldn't get that to work in GR5, but I really should try again.
As to the Loop Machine, it looks like they removed it in GR6. Maybe because it didn't work properly and they didn't think enough people used it?
Who knows. I'll ask support if they ever get back to me.