Outstanding problems so far:

Read only FS:
Sorry, I misread the output of 'mount'. The 'a' and 'e' look quite similar
to me in the small BSD font. The correct output has /usr on wd0e.
Furthermore, I was able to write a file using 'root' and 'who > test'! If I
try to do this with another user, then I get a 'Permission Denied' error.
This doesn't surprise me as I don't know how to set up a user properly (the
manual helpfully tells me to set up a user, but not how to do it). In
addition, cat /etc/fstab produces similar information to what I now believe
that it should.

X:
I followed your instructions carefully, and then typed 'xdm'. The machine
told me that only root wanted to do this. I then tried 'startx', whereupon I
was given an error about my display. Logging on as root, I actually managed
to start X using 'xdm'!
                                                                              
New Problems encountered:
As above, I don't think I set up a user correctly. To which group should
they belong? I currently have two users as 'nobody' and 'no group'
respectively.

In X, every now and then the window becomes filled with esoteric messages
along the lines of 'keybd repeat 6 times recieved'. Is this normal? Do I
need to increase the maximum number of processes or some such thing?

My prevailing attitude:
Contrary to popular opinion, I am not really upset or demoralised. When I
first failed to use RiscBSD I was slightly dejected as it appeared that I
had bought a load of hardware and software only to find them useless. Being
new to the Internet, it took me a minute to realise that perhaps someone on
the mailing list might help. Well! The response has been overwhelming. You
should all be canonized for giving up valuable time to help lost souls like
myself, without thought of personal reward. A thousand 'Thank you's.