NextGen Gallery prroblem – Rendering of template gallery.php failed

I fixed this by finding in nggallery.php:

define(‘NGGALLERY_ABSPATH’, str_replace(“\\”,”/”, WP_PLUGIN_DIR . ‘/’ . plugin_basename( dirname(__FILE__) ) . ‘/’ ));

And I replaced it with:

define(‘NGGALLERY_ABSPATH’, str_replace(“\\”,”/”, WP_PLUGIN_DIR . ‘/nextgen-gallery/’ ));

But now the slideshow fails and all the pictures are in one column.

You have to modify how both NGGALLERY_ABSPATH and NGGALLERY_URLPATH are defined in order to solve this error. These are defined in nggallery.php around line 209 and 210.

The following definitions work for me..

define(‘NGGALLERY_ABSPATH’, dirname(__FILE__) . ‘/’ );
define(‘NGGALLERY_URLPATH’, WP_PLUGIN_URL . ‘/nextgen-gallery/’ );

I believe the problem is actually down to the function plugin_basename() not returning the expected response

this might help, got it from an earlier post,

Let me note :

if you add the gallery.php (form the plugin folder) to

{wordpress dir}\wp-content\themes\your theme directory\nggallery\gallery.php

then you can call it with [nggallery id=x]

if you need another template use the tag [nggallery id=x template=mysample]

and NextGEN Gallery look for a file in

{wordpress dir}\wp-content\themes\your theme directory\nggallery\gallery-mysample.php

There might also be other relevant discussion on gallery ID and templates read the whole thread for more.