Catchable Fatal Error

Hi.

Just created a gallery with three images, works fine.

Add images to the existing gallery and all the added images result in:
Notice: Undefined offset: 0 in /var/www/html/new_site/wp-content/themes/enigma/functions.php on line 332

Catchable fatal error: Object of class WP_Error could not be converted to string in /var/www/html/new_site/wp-content/themes/enigma/functions.php on line 333.

The first three images still display and link correctly but the added images only display as thumbnails and when clicked on return the above error.

Suggestions please?

Cheers.

Ken.