Is the powerline adapter connected to a modem or router? Now both of the laptops can be connected at the same time?

I have similar problems. Having just upgraded to satellite broadband (having finally given up with BT) I decided to upgrade my Powerline kit from some old (but working netgear wireless) and as the satellite provider (Tooway) supplied a TP-Link router decided to go with the same manufacturer. I bought a TP-Link PA411 AV500 kit of 2 hard wired powerline devices, and one TL-WPA281 AV200 wireless N Powerline extender.

The two hardwired devices work fine, one connected to the router, and one to the Sky+ box. HD movie streaming works fine. The wireless extender by comparison seems only able to have one wireless connection at a time, and as we use it for 2 laptops, 2 iPhones, and an iPad, one is always trying to connect which just knocks off the presently connected device. Having originally gained access to the web configuration page I can now no longer get to it.

I have now reconneced the Netgear and at present have both laptops and the iPad all connected and working. I could leave it like that but that's not the point is it?

I'm going round in circles.

that is weird.
How do you connect the powerline adapters to the other devices?
for example, A connected to the router, B connected to the PC..