Oh that progress meter! Yeah that is actually just a loading animation. If it doesn't go away, that means that it is waiting for the LinkMeter to respond with the graph data. It can hang indefinitely at this step if there are too many connections open to the router at once. There is a limit of 2 simultaneous connections (due to memory constraints), and the streaming status update keeps 1 open. Make sure you do not have the status open from any other device, or have it open to the Internet where a random person might be hitting it too.
If you can't find who the other connected person is, you can telnet/ssh into the router and run `netstat -n | grep :80`
Code:
root@OpenWrt:/# netstat -n | grep :80
tcp 0 190 192.168.2.3:80 192.168.100.139:58686 ESTABLISHED
The IP address on the right side is the IP address of the host preventing you from connecting.