Here's some more info.
Dreamweaver: Version 10.0 Build 4117
I've copied all the Dreamweaver files to another computer, and reset my WA activations so I could test the problem on that laptop, but am still getting the same response (brand new installation of eCart 4.5.2).
I can see that the database connection is working properly as the first table under the heading "Downloads" has two columns, consisting of the two entries in the database (the second table beneath this is static text).
Thanks in advance for any help you can give!
PS I have 7 years experience of HTML/CSS, 3 years of PHP and 1 year with MySQL. I thought I knew a reasonable amount, but this has got me stumped...