Well, I have now purchased a X-over cable and the Toshiba connects to the Mac as before, which is good.
I still can't make the Mac to Tosh connection. I'm
still not convinced about my usage of Username and Password. This is what I get when I go 'Connect'.
Workgroup/domain is automatically filled, as is Username. As far as I can tell I just need to enter my Admin. password. Sorry for being repetitive but at least I can rule out the cable.