Just to report my experiences: I finally got together my two cables and adapter (from NeoStormer's links--thanks, Neo!), AT&T Motorola Atrix Lapdock, and MK802 miniPC (1GB w/tiny holes in case and barcode stating memory type). I have to say that the hot 5 pin USB fitting that connects to the lapdock seemed a bit ill-fitting and wobbly, making me think that I might damage the lapdock connector if I forced it on. I examined both under high magnification and decided to give it a try. It booted into Android 4.0 as expected, or Lubuntu when I inserted my microSD installation (thanks, AndyKirby & Miniand!) but didn't give me any control over the keyboard and trackpad. (Does this mean that the #4 pin is not functional?) Also, the slightest bump to the wire would cause it to disconnect and have to be rebooted. I removed this mini/micro USB cable and plugged in a standard USB cable from the end of the 802 to the lapdock USB hub and, of course, got the exact same result: display OK, no keyboad or trackpad control, booted into Android, etc... so the "Hot Mini-A 5P 5pin USB Male to Micro-B 5P 5pin USB Female extension cable" seems to be just functioning as a normal USB.
I think maybe I just got a slightly damaged cable or a quality control reject, etc, and will reorder a couple or 3 more from the same place (at $1.99 including S&H, why didn't I do this to start with!?). Does anybody know another, maybe even quicker source? or any other source whatsoever? ... or have a spare proven cable to sell for maybe... US$10.00 or so?
On a more upbeat note, while stewing over what I would use for a keyboad, I ran across my forgotten 8 or 10 year old Adesso "Wireless SlimTouch Mini" 2.4GHz keyboard with track pad, put in new AA batteries, plugged the receiver into the 802 and... it instantly worked! Also it fits fairly neatly on top of the Lapdock keyboard, so I'm now using the outfit with a double-thick keyboad until I can get another cable

This keyboard is also very handy with the 802 hooked to my TVs.
Thanks again to everybody for making this fun possible.
Doug