I was able to get past the mysql error by dropping the schema. The instructions next to the field to specifying the schema name says that it must not exist, yet the error message says the the user needs to be able to create one. Might I suggest this be clarified, or the CREATE DATABASE statement be modified to include IF NOT EXISTS...
The other error about filesystem permissions, I am still at a loss about, however. I've tried removing the photos directory and setting src/html to world writeable, but that didn't help.
documentation/guides/InstallationUbuntuApache.sh sets the user of the photos directory to the apache2 user, which I've done...
mkdir /var/www/openphoto/src/html/photos
chown www-data:www-data /var/www/openphoto/src/html/photos
What am I missing?