Raj, login web interface of MR3220. On Status page, under 3G/3G, there is an IP address. Is it what you are looking for?

Before upgrade, reset the device first. Try different web browers like Chrome, Firefox etc., or try different computers to upgrade it. After upgrade, reset it again and check the firmware version. By...

On their website, there is where to buy info? http://www.tp-link.com/eg/where-to-buy/

PA101 is not compatible with either PA211 or PA4010. In you case, two PA101 can be paired; PA211 and PA4010 can be paired; four units cannot work in the same powerline network.

Umm, you mean, bypassing PA4020PKIT, wired connection and wireless connection to the router can work simutaneously? It is so strange... Try to reset both of them with utility and rename for both....

When connection drops, how about status of WAN light? Since you can login its web interface, on Status page of MR3420, WAN is showing Connecting? Provide a screenshot here. Besides, the system log...