Maybe you can do a test by some P2P download software... If still the same, you can try to downgrade it to the factory default firmware to do a test...

No. I heard that TP-link has a software called sniffer, you may send a email to them for that....

Take their compatibility list as a reference: http://www.tp-link.com/common/compatible/print-server/

To select the operation mode of the TL-WA801ND first: http://www.tp-link.com/en/article/?faqid=442 Install the TL-WA801ND as a Repeator: http://www.tp-link.com/en/article/?id=250...

See what I found here: http://www.tp-link.com/en/article/?id=400

connect your computer to the TL-PA211 with a lan cable, and then install the TL-PA211 utility, then I think the utility will detect the local device. If not, try another cable and copmputer...