Fatal error Photo Gallery

I am using the free version of photo gallery by Supsystic and now I get a Fatal error. T think it started when it was updated 5 days ago to version 1.15.11. The website works when I deactivated the plugin, without the galleries, but I get the error below when trying to activate it.

It is for a website showing someones art, so I am afraid to do to something that will crash the site or the galleries. The owner has put in a lot of work to make the galleries. Please help me.

WP version: 6.0.2
PHP version: 7.4.30

Fatal error: Uncaught Error: Class 'Rsc_Mvc_Module' not found in /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/src/GridGallery/Featuredplugins/Module.php:4 Stack trace: #0 /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/vendor/Rsc/ClassLoader.php(118): require_once() #1 [internal function]: RscSgg_ClassLoader->load('GridGallery_Fea...') #2 /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/vendor/Rsc/Resolver.php(314): spl_autoload_call('GridGallery_Fea...') #3 /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/vendor/Rsc/Resolver.php(276): RscSgg_Resolver->findModules('/home/bolmelrj/...', 'GridGallery') #4 /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/vendor/Rsc/Resolver.php(82): RscSgg_Resolver->getModulesList() #5 /home/bolmelrj/public_html/wp-includes/class-wp-hook.php(307): RscSgg_Resolver->install('') #6 /home/bolmelrj/public_html/wp-includes/class-wp-hook.php(331): WP_Hook->apply_filters('', Array) #7 /home/bolmelrj/public in /home/bolmelrj/public_html/wp-content/plugins/gallery-by-supsystic/src/GridGallery/Featuredplugins/Module.php on line 4

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