FOUND IT!
A very slight (thankfully to this point) leak at the heater core inlet and outlet lines from the engine near the thermostat.
As you'll see in the pictures the coolant lines are about an inch but the clamps used at the factory were too big and when locked in were too large to clamp the rubber at all. (Someone at the factory needs a lesson from our Buddy Greg to do a proper install

).
Thankfully I had a couple clamps (tho larger than I wanted) to do the job -- screw type that I like best. This is Canada Day and no body is open for parts or service.
Not the easiest of locations to work on especially with a hot engine, but at least I found the leak(s) and fixed it.
As Mike suggested, I took off the engine splash guard and found residue (tho miniscule) of a leak. I traced it back up to the top of the engine and voila!: 2 loose clamps. I thought that's weird.......and then to the ends of the heater hoses which of course were loose.
Could have been much different if I'd been on a trip and the heater hoses had let go. I dodged a bullet there for sure. I really can't believe that these hoses hadn't leaked more.
Anyone else with an '11 -- you might be wise to check those heater hoses for clamps that fit and are tight.
The other thing I discovered was the engine splash guard: Great idea of fastening it to the engine area Ford! In solid with only 4 twist clamps.
A whole lot easier than other brands that I've struggled with that have many many clips and such to get that thing off.
Kudos to Ford for that at least. (hose clamping is another story--

)..
Thanks to all for suggestions and especially to Mike for his suggestion.
Cheers.
First is the engine splash guard that I removed.
A closeup of which reveals the evidence:
and then the upper side with the wayward clamps and hose ends