If he was running into a DX issue, I think he would get a crash or an error. Just getting a black screen normally indicates a client version issue. For example, he mentioned trying to use RoF to connect to EZ server, but EZ does not have the RoF client enabled yet, so that would cause him to get just a black screen on the RoF client. Storm Haven does have RoF enabled and it works fine, so if you have the correct RoF client that shouldn't happen.
There are a few reasons why you can get the black screen when connecting to a server, which are listed in the FAQ here:
http://www.eqemulator.net/wiki/wikka...QEmuFAQ#QLinkR
The first thing you should check is your client version per this:
http://www.eqemulator.net/wiki/wikka...ClientVersions
It is possible that Steam updated to a more recant patch of EQ than what we consider "RoF" as far as EQEmu compatibility goes, or maybe you patched it by mistake. I just downloaded a fresh copy of RoF from Steam a few days ago and mine is the correct version still, but they could have changed it since then (though I kinda doubt that).