Thank you Edge. That all worked perfectly.
Only one thing though. At the final questions section I entered the host name as 'www' which I believe is ok - it shows that in the installation instructions you sent the link for - but, and here's my mistake I think, for the next question, 'Please enter the domain' I entered the name of my current website (xxxxxxxxxxx.com). That does not work of course as that is already being hosted by a commercial company. The problem is that I now cannot log in to my ISPConfig control panel. I presume that there is a configuration file somewhere where I can edit out my mistake and replace it with something else. Can you point me to where please, and does the 'something else have to be entirely fictitious or one that is registered. I have an unused (not hosted anywhere) .co.uk name that I could use if necessary.
Sorry for being so stupid