Thank you for your quick response. It is working now, with a few issues. I deleted the FB App and started over. It seems that FB wanted a new app because the site URL is not the same as I used on the old site (because I am in development stage and it is in sub-directory of public_html called CMM).
The issue I'm having now is that there are some white blocks in each Album (like I have on the old Joomla 2.5 site) where the thumbnails should be. Most thumbnails are fine, but there are some white blocks. Also, I have changed the Gallery/Settings, but the Album Title doesn't show up on the Gallery Page - see url...
creativemathandmusic.com/CMM/index.php/about-cmm/gallery
thank you for your help, ...paul