Video issues with YDL 2.3

[Greg Dougherty]

Ok,  I have YDL installed.  During the install, I told it to consider my monitor
to be 800 x 600 with 16 bits of color.  That worked.  So I ran Xconfigurator and
told it to do 1024 x 768.  Now it gives me a virtual monitor of 1024 x 768, on a
monitor that is only displaying 800 x 600. :-(

So, in command line mode I started playing with fbset.  I checked out
/etc/fb.modes.  I told fbset to use the mode "800x600-70", and everything
worked.  So then I tried "1024x768-75", and THAT worked. :-)  Then I ran startx,
which failed because it couldn't find a monitor. :-(  Went down to "800x600-70",
startx still failed.  WTF?

So, my questions:

1: How do I get Xconfigurator to change the monitor's real dimensions, not the
virtual ones?  Does Xconfigurator use /etc/fb.modes?  Can I use fbset with X?

2: How do I set my command line environment to default to a different mode?

3: On a different topic, I note there's a directory /mnt/macos that I did not
create.  What does YDL use that for?

TIA,

Greg