Loading Game in Windowed Mode

[CmaN]

I really have no idea. A few things to try/mess with:
1.) First, why is your fullscreen mode black? I know you're wanting to work in a window, which is just fine, but that shouldn't be. If this is a new machine, have you already updated the graphics drivers?
2.) When you first launch the client, click 'Options' and go through the prompts.. it may fill in some values somewhere or modify/create eqclient.ini. I don't know for sure, but it wouldn't hurt.
3.) I think if you can get logged in to a character, and then /q and restart client, more settings in eqclient.ini may get populated.

Just some things to try. I'll keep thinking though!