I apologize for my very delayed response.  Other things got in the way.
For some reason, the Denon AVR-X4000 device upgrade doesn't work on this remote with either my Denon X3200 or X4400 receivers.
I've learned several more Denon device input keys (last two columns are OBC then Hex Cmd):
- 1	Blu-ray		Denon Audio	SoftD		45	38278	Denon-K	4	1	721	77 4B
2	GAME		Denon Audio	SoftE		45	38278	Denon-K	4	1	725	75 4B
3	Media Player	Denon Audio	SoftF		        45	38278	Denon-K	4	1	726	79 4B
4	TV Surround	Denon Audio	Soft10		45	38278	Denon-K	4	1	722	7B 4B
5	Aux1		        Denon Audio	Soft11		45	38278	Denon-K	4	1	729	76 4B
6	Aux2		        Denon Audio	Soft12		45	38278	Denon-K	4	1	730	7A 4B 
The RMIR file has been uploaded to 
http://www.hifi-remote.com/forums/dload ... e_id=25904.
Device 2857 / Denon Audio is the device that was learned from the Denon remote.  I tried to incorporate the learned keys into this device.  Again, the Hex codes do not translate to the same OBC codes as the learned keys.
The learned device works fine.  The learned keys work fine.  But they appear to be using different protocols.  Should I just stick with what I have and not try to integrate the learned keys into a device?
Device 1400 / Denon X4400W is the non-working device upgrade.