Piwik 2.14.0 RC CoreUpdate slow ? hang?

How does the admin area auto update work, when i click update/install for 2.13 to 2.14 RC it goes to link at upgrade via /piwik/index.php?module=CoreUpdater&action=oneClickUpdate but just has spinning working icon in Chrome 43 and nothing else ?

Is there a progress log or some settings to troubleshooting what’s going on in background ?

Also is there any particular ports need opening up and/or ips need whitelisting? I have CSF Firewall enabled.

edit: looks like if i refresh the page, i get the

thanks

George