New RiscBSD user seeks help...

Some hardware info:
  RPC600 + SA, 24 + 2 MB
  Quantum Fireball 3.8 GB (7480 cylinder) - as master

First of all, bb_riscbsd reports a filecore partition size of -3121 
blocks. Should it be negative? I used the hformbeta app to give RiscOS 
about 2.5 GB (5200 cylinders).

Booting BSD from inst12.fs I then set the partitions on wd0 as follows:
  /    41 cylinders
  swap 49
  /var 25
  /usr 2165 (all that was left)

The RiscBSD partition offset is 5200, the number of blocks in the RiscOS 
partition. Should it be 5201?

Re-boot to RiscOS. Trying unixfs, e.g unixfs.wd0a, I get:
  5
  Error reading file system


So, resorting to floppies I can get some sets installed. Got the rest by 
FTPing from BSD; X etc running nicely. Then crunch... disc label corrupted.

Is there a way to fix this without going all the way back to bb_riscbsd? 
I didn't seem to be able to do anything much, with it not being able to 
mount '/' owing to the bad disc label.

Any ideas how it might have happened in the first place?

Thanks,

Simon M.

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

Dr. Simon J. Melhuish
N.R.A.L., Jodrell Bank.
http://www.jb.man.ac.uk/~sjm/