I am also using a SG server.
Ordered the server just a little under 24 hours ago, and I can't get into the server at all.
I don't get the black screen, and I've no issues seeing the server under Steam, but it will disconnect me every time I log in.
Sent in a ticket, got a reply that they are fixing it, but it is extremely frustrating not to be able to log in to the server at all for almost a day now!