GS/OS boot error

[John Le Febvre <John@klatch.demon.co.uk>]

I have been unable to boot into GS/OS recently.  Regardless of whether
I shift boot or not, I get a "Sorry, system error $1104 occurred
trying to load the next application" when it is trying to load Finder.

When I booted into ProDOS instead of GS/OS I could run programs but
one of them (can't remember which one now) gave me a "ProDOS MLI
Error 54 (I think) Main directory is bad"

Now I am assuming my Sys vol is trashed.  I tried to load GS/OS
(6.0.1) from floppy and it too crashed when it tried to put the first
hard drive vol icon on the desktop.  5.0.4 was the same, but 
strangely, 5.0.2 would let me in.

I think this stems from me upgrading my ZipGS and maybe that the
GS bombed while accessing the hard drive one time.  It is pretty
stable now at 9/32 (from 7/32).

OK.  What am I asking?  Is there a way I can fix this or at least
confirm my fears?  I guess I may have to purchase something like
ProSel-16 to fix things so an address and price would be useful.

One more thing - why does this have to happen when I'm trying to
get Wolf3D up and running? ;-(

Thanks for your help
-- 
John.
john@klatch.demon.co.uk