Xclaim + Google DNS
Something I've noticed is Xclaim access points ping Google DNS in order to test internet connectivity - if this ping fails they'll refuse to speak to CloudManager. I've got an access point in a location where both external DNS is blocked and pinging Google DNS is blocked also (due to the fact Android devices will default to it) and thus the AP never comes online on Cloudmanager.
This appears to be a pretty bad oversight - not sure why it does this. Is there a workaround to get the AP online? If I allow Google DNS it works no problems however can't leave it enabled on this connection.