worked but did something else
I did as you suggested and did the delete of the Mac.dat file 2 times, then I tried again using CSS Form Builder to do the edit of the form with the directions for editing an existing form. This time it worked and I did not get any errors, as before.
BUT, the form layout was would need a lot of editing to get it back to the way I had it working before. So I took a different tactic for adding only a Captcha to my existiing form.
Using CSS Form Builder, this time I opened the form page in DW. I put my cursor below and just outside of the existing form. I then used Form Builder to create a new form which was only a Security group.
Then I opened the new form with the Captcha and took out only the <ul>to</ul> (not taking the HTML for the new form). Then I pasted the Captcha code into the existing first form just above the submit button. I changed a couple of form item references, tested and it works.
This was much easier since I did not have to do any layout corrections to my existing working.
Take a look at reg.php
Thanks for you help on fixing the issue in DW.