Critical systems not updating

Hi all,

I am trying to set up the critical systems for our hobbit installation
but I cannot update the records, a previous user made 3 test ones but I
can't alter or drop them, though it does update the record when I do so
the next time I go to the same record it reverts back to the original
version, does anyone know where they are stored so I can delete them on
the server itself?

Thanks,
Jason.