I downloaded the free Native Software on Saturday by Sunday night all I got was the spinning wheel when as soon as I selected Native Plugin.
I read through the replies on a few forums and tried the quote telling me to load my DAW then turn your WIFI off / disconnect from the internet select Native Plugin which then gives you the line 6 login pop-up. Turn your internet / WiFi back on and enter your username and password. Native should then be up and running.
hope this helps.