The thing that worked for me is that apache was not generating the key for a new certificate, so that was something outside of moodle but moodle needed that encryption certificate to pass along to the other moodles in the network. I don't know if that applies to anyone here, although I saw messages (i.e. Payload and parsing errors) like the ones you've noted in this this thread. Here are links to 2 other moodle forum discussions that helped me: http://moodle.org/mod/forum/discuss.php?d=83808 and http://moodle.org/mod/forum/discuss.php?d=75556. I'm using xampp apache, so there is a /xampp/apache/makecert.bat file that enables apache to generate the keys. You can open the makecert.bat file to see what it's doing if you're not on xampp.