I've just reset the router to factory settings and still no joy, I can't access the QoS Engine for the life of me.
I've tried:
Updating to the latest beta firmware. (after updating QoS showed up but after opening and closing FF browser it went away)
Accessing home page with all of my web browsers, FF (standard and Safe Mode with no plugins activated) , Chrome and IE
I've tried on my wired PC, Wireless Laptop and Safari on my I pad
Power cycling the router
Resetting the router to factory settings and setting it up again
So far nothing I've done has worked. This is what the page looks like when I go to it, note, this screenshot was made prior to updating to the beta firmware:
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While I hate to call tec support that's my next step I suppose.