Database error while zip upload

Hey guys,
I hope you can help me. Today, I’ve installed a fresh version of WordPress on my webspace. After that I’ve downloaded the latest NextGEN plugin version 1.8.1 and installed this as well. Everything fine for now. But when I try to upload a zip file I get a database error which tells me that the upload was successful but that no new record for the new gallery could be added into the database table. I’ve searched through the source code a little bit and found that the error was thrown by a missing “slug” string in the sql statement in admin/functions.php on line 172

if (!$gallery_id) {
  $result = $wpdb->query( $wpdb->prepare("INSERT INTO $wpdb->nggallery (name, path, title, author) VALUES (%s, %s, %s, %s)", $galleryname, $galleryfolder, $galleryname , $user_ID) );
  if (!$result) {
    nggGallery::show_error(__('Database error. Could not add gallery!','nggallery'));
    return;
  }
  $created_msg = _n( 'Gallery', 'Galleries', 1, 'nggallery' ) . ' <strong>' . $galleryname . '</strong> ' . __('successfully created!','nggallery') . '<br />';
  $gallery_id  = $wpdb->insert_id;  // get index_id
}

Is there a “trick” to avoid this error message or how can it be fixed otherwise?

Greetings
Marc