Even though I have placed and centered photos between paragraphs,, and they stay in position on iWeb,
when I go to publish, they are still where they belong on the iWeb "original", but when I check the site using onee of several browsers,
I find that photos have shifted and are now blocking copy.
This can be seen on website www.william-penn.net
What is causing this problem and how do I keep the photos where I want them?

Hi Erik,

you may want to read Chapter 1.4 of this page:
http://iwebfaq.org/site/iWeb_Troubleshoot.html

It probably happens because different browsers render and read copy slightly differently.

Regards,
Cédric