I discovered that if you have sent a user a message from the supplied backend Admin Panel, it does land in their box, and they get a notification for it. But they are unable to open or respond to it... ( the class makes a link cursor appear, but there is really no link there)

Aside from that, I find the UI ergonomics of that panel are a bit difficult.



The actual message link (message text) is an inconspicuous light grey, and yet the username is bold and blue and highlighted in such a way that your cursor is drawn to it like a moth to a flame! So I find myself bringing up the user's profile, rather than the message content.
I suggest that the message content link should be Underlined, and/or highlighted with a background color, so that it is more obvious that you should click there to read the message (after all, that's the primary purpose of the panel - to deliver the message...)

And I notice that the message content link is also hooked to the red/green 'online status' symbol - which I find a bit counter-intuitive ( If anything a link there should go to the user profile...)

Sadly I can't check this now... had to roll this DEV server back to the previous version