Since sending the previous post I've ditched the original install of PowerCMS and started over. I then changed the admin/index.php page so that instead of saying:
mysql_select_db($database_localhost, $localhost); at line 42
it now reads:
I then tried opening admin/index.php in the browser from inside MAMP and it took me to the right page (although worryingly without having to log in) and the next problem is that when I click on either of the View/Edit Content or Insert New Content tabs, I get a 404 with this URL coming up in the browser, which suggests that the /CMS/ setting for both local and remote is wrong:
it should be: contents_insert.php
and if I add the missing word into the nav bar, it brings up the correct page. So... I assume that this is a case of something adrift in the WA_Globals.php page settings - am I right, and if so, what should I have in there to put it right?