OK... here is the issue. My RG is all the way on one side of my house (opposite of my new garage I need TV service in) and I am sure the WAP is not powerful enough to get a good signal out to my garage. Can I connect the WAP to the back of a coax fed uverse receiver and use that for the connection to my RG?
The wap has to be directly connected to the rg gateway, now you could run a cable from the rg closer to your garage and then plug the wap into that cable.
Can you plug it into a stb, yes you can but your connection will suffer and not be very good so that is why they told you no, but you could do it in the short term, but don't call in for a tech dispatch because you would be charged for the truck roll
Technically your not supposed to run a WAP off a stb but I have seen them work fine as long as you don't plug it into the DVR the DVR can't pass recording through itself. Best option is 2 way splitter behind stb coax to stb and hpna to Ethernet adapter plug WAP into that. I've seen both ways work fine even if they're not "technically" supported
Get a couple POE plug link adapters, they work great for this application with no wiring and it's usually cheaper than having a tech run a line to a fixed spot, you can move this around to the outside if desired or a neighbors backyard .
I went ahead and ran Cat-5 out to the garage and put the WAP out there. I dropped some conduit in the hole after they ran the power wires from the house. Cost a few bucks but it wasn't too bad I guess.... didn't even know they made Coax HPNA to Ethernet adapters.. oh well..