Did you check the specification for TL-PA511KIT on their website? Power Consumption Maximum: 7.56W (220V/50Hz) Typical: 6.80W (220V/50Hz) Standby: 1.16W (220V/50Hz)

This is what you need? http://www.tp-link.com/en/article/?faqid=383 TD-W8980 is not capable of that function.

Telnet doesn't work because it is not enabled I think. Start—>Control Panel—>programs and Features-- Turn Windows Features on or off. Choose telnet client, Press OK. It should not but some special...

Try to change a password to disable security to test. Other wireless clients are working OK?

It seems that line synchronization has a problem. Did you try to change DSL mode to ADSL2 or G.dmt? Of course, you can follow TP-LINK support's advice to replace it.

Not quite sure if it will be working...You want to use a wireless modem router to replace the bridage modem and access point, right? The modem router can be configured as an access point with DHCP...