All ports are equal.

Tried to plug the camera to other POE ports? If you just connect it and disconnect other cameras, does it work? Maybe it is a camera issue? Did you contact camera support?

Can you provide a screenshot? Did you secure the powerline network? http://www.tp-link.com/en/faq-258.html

TD-W9980B is for Germany Market only and it has only firmware in German language, no English firmware.

Try to enable WLAN Autoconfig and try again. http://www.tp-link.com/en/faq-306.html If it doesn't work, uninstall the driver, uninstall anti-virus software and disable Windows firewall. Later try to...

The rate in utility is not the internet speed but transfer rate between two PA2010 units. 168Mbps is quite normal. The real internet speed is given by your ISP. You'd better test it bypassing...