When I invite someone the also wouldn't recieve an email.
But my pending invites screen still has one entry/email.
Mine showed up initially as well, but within 24 hours all the pending invites disappeared.
No email sent either after my invites. Also, I face the same situation described by Clifton Labrum right after closing the overlayer.
Short precision, when I try to enter again an email that disappeared, I got this error message.
An invitation already exists for this user and this network
No invitation emails are being sent.
No notification emails are being sent.
So the conclusion seems to me is no emails OF ANY KIND are being sent. The whole email thing is not working.
Hopefully someone might look into this urgently!