I have a solution for you regarding why your router is not "measuring your uplink speed".
I found this out recently because I just got a new SB6121 Docsis 3.0 cablemodem - one which is capable of connecting to my dgl-4500 router at Gigabit speed.
That is the issue.
My old cablemodem could only connect at 100Mbps, and the router would always "measure my uplink speed" no problem.
Well, now that I am connecting to the router at 1000Mbps, the router simply says "Not Estimated".
This, of course, affects your QoS settings, since QoS is enforced on UPlink only, and if the router has no reference of how much bandwidth it has to play with, then all the QoS rules you set are worthless.
I use Vonage for my home phone. I was torrenting, etc to drive up my usage of the link as a test.
I found that the quality of the call was bad, even though my QoS setting for the Vonage traffic was the highest priority.
This is what led me to troubleshoot it - as I knew there was a QoS issue somewhere - and the only thing that had changed was the cablemodem, and the speed of the ethernet link between it and the router.
I tested this by changing (in Advanced Network) my WAN port speed from Auto 10/100/1000 (which now was connecting at 1000) - to 100.
As soon as I changed it to 100Mbps, and the router rebooted - well low and behold, the router stated it was measuring the uplink speed - and then upon going into the QoS page - it reported the speed of 1055 Kbps. (just like it always used to - when I had my other cablemodem that could only connect to my router at 100Mbps).
I tested the router, and my QoS settings with the WAN hard coded to 100Mbps, (and "Automatic Uplink Speed" checked).
I tested the router, and my QoS settings with the WAN set to Auto 10/100/1000, (withOUT "Automatic Uplink Speed" checked) - and a manual entry of 1055 Kbps in the Manual Uplink Speed box.
Both configurations worked equally - and allowed my QoS settings to "work", since the router had an uplink speed "value" to use, now.
I ended up staying with using the manual entry in the Uplink speed box, only because I liked the fact that I was now connecting at Gigabit speed (although in all practicality, I don't need that speed) - but also because the LED on my 6121 glows blue for Gigabit and orange for anything less - and I prefer blue !
I hope this helps my fellow D-link router owners !