Undefined index: cache_dir error

Hi,

I am on the Genesis theme with the Dynamik Website Builder. I have the plugin working properly on another site with the same theme properly.

However on another similar site I am getting the following error output when I try to display a gallery in a post:

Notice: Undefined index: cache_dir in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 140

Notice: Undefined index: cache_dir in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 143

Notice: Undefined index: cache_dir in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 148

Notice: Undefined index: cache_dir in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 149

Notice: Undefined index: cache_dir in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 153

Warning: mkdir() [function.mkdir]: No such file or directory in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 505

Fatal error: Uncaught exception 'UberGalleryException' with message 'Unable to create cache directory, please manually create it' in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php:506 Stack trace: #0 [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php(207): UberGallery->setCacheDirectory('.//photos...') #1 [server path masked]/plugins/simplicity-gallery/simplicity.php(138): UberGallery->createGallery('.//photos...') #2 [server path masked]/wp-includes/plugin.php(199): _simplicity__show('') #3 [server path masked]/wp-includes/post-template.php(166): apply_filters() #4 [server path masked]/themes/genesis/lib/structure/post.php(310): the_content() #5 [server path masked]/wp-includes/plugin.php(429): genesis_do_post_content('_simplicity__sh...', Array) #6 [server path masked] in [server path masked]/plugins/simplicity-gallery/UberGallery/resources/UberGallery.php on line 506

This site has the wp-content folder renamed.
Any help is appreciated! Thanks!

https://www.ads-software.com/plugins/simplicity-gallery/