Dmollo,
The Error Checker is likely timing out because you're using a non-standard port to serve your page. The error checker is meant to only scan sites on the standard port 80. I just manually checked your site, and all the tests the Error Checker would run would pass.
As for your issue with saving an object, I'm not sure what's causing that. A white page is almost always a PHP Error page. Your server may be configured to not let Joomla override the Error Reporting settings. In that case, you'll need to update your PHP Configuration to enable error reporting or check your PHP error logs on the server to see what error is actually being thrown.
The other possibility is that you have mod_security enabled in Apache. We've heard some reports that having mod_security is causing issues when saving new Open Graph actions and objects. We haven't been able to evaluate why. Can you check (or ask your hosting company) if mod_security is enabled, and if so, temporarily disable it?
Thanks,
Alex