I'm out of ideas at this point.
Hopefully someone else has some something for you.
I suppose it could be a corrupt installation of XAMPP. I've never heard of that before but I guess it could be possible.
Ready for this? After futzing around for hours on this I discovered that the .htaccess files in my various site folders in htdocs folders seem to have been causing the problem. When I arased them all sites worked perfectly. The strange thing is that they have been there forever. I wonder if Adobe made an update to Dreamweaver that causes this rendering failure in Live View on .php files when .htaccess files are present.
Anyway thanks for taking the time to help out! I appreciate it.