Ok back from booting the Presario upstairs with Knoppix 5.0.1 live CD.
Success! It confirms that it works with the live CD as well.
(I gave the full details just for the live CD in the Presario in my first posting so as not to over-load the post, with only passing mentions for VMPlayer etc. as it was completely representative of all test modes). I was interested to note that the VMPlayer-hosted image has VMWare's own 'pseudo' MAC hardware address - which makes sense of course - and its own IP address was allocated OK under DHCP, which I re-used in the non-DHCP set-up.

I'm using VMWare's recently released VMPlayer VMware-player-1.0.2-29634.tar.gz on Knoppix 3.7 with the libraries updated to Debian Sarge. So far I have found it to be 'transparently' representative of a 'real' set-up, except that the sound card doesn't work, but I haven't needed that for my applications.

Once again, many thanks for your help.