There is no "sides" to where you use those powerline adapters. The extra 8010 you get can just as well be used on the far side of a powerline network, on an endpoint device. It just so happens that...

This is a user forum, not a vendor support chatline. Besides, to my experience, disconnects rarely are actually caused by the PLC powersave feature. It's just the standard answer from vendor customer...

Think of it as a PLC that has a LAN switch and a WLAN AP integrated. The TP-Link website even has a "simulation" of the WLAN AP user interface - have a look!

Disable the 2.4 GHz then, or assign two different SSIDs and connect your stuff to the SSID you gave to the 5 GHz part.

Roaming is something the client devices need to solve on their end. Some are quick to switch when the signal goes weak, others cling to whatever they got first until they lose connection. You should...

Ah yes, that's actually a common miss ... and the support section on the product's web site doesn't exactly help either, for it just lists the 4530 unit. LED and CCFL lights do contain driver...