Description of Problem: Forwarding X connections (which doesn't work) attempts to use /usr/spool/sockets/X11.
This directory should only be checked if there's no socket in /tmp/.X11-unix, and none in /var/X/.X11-unix, either. This leads me to believe that the DISPLAY environment variable is set correctly on either the server or the client. What are the values of the DISPLAY variable on the client and in the session started by the server? Is X11 forwarding enabled?
Uh, yup. I finally strace'd the client (under *Cygwin*, are you starting to see the picture that I'm going to paint?), and yes, it's the client. eXceed (this is at work, under Winsux-2000-times-worse) doesn't know about Cygwin, and it doesn't know about putting sockets in the file system period (AFAIK; does NTFS even support them?). So it's the Cygwin client that's pissing and moaning (it also bitches about not finding /usr/X11R6/bin/xauth) about this. I think I'll just install XFree86 and be done with eXceed (which most times, does eXceed my expectations ... for really annoying behavior, that is). CLOSED. I'd mark it myself, but I don't have button on my UI in Mozilla.
Closing.