I have done some more experimenting. I went back to the earlier version of PowerGallery and reloaded the database and it is all working. I set up a test folder and uploaded the new version of PowerGallery, imported a copy of my old database into a new database. I see the image information in the pg1_gallery_images table. Then I refresh the main admin page and the table is set to blank. We tried this twice - the table was erased both times.
I get this message on the admin page:
Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in /usr/www/users/slow/pg/admin_gallery/common/functions.php on line 566