Change Number of Pages Displayed in Access Level

I need to select several pages that are in one of my access levels in this plugin. But the plugin only displays the top 50 most recent pages. How do I select pages for a specific access level when I can only see the top 50 most recent pages?

I need help modifying this default page number to display all of my pages so I can select specific pages from being protected.

Thanks,
Shinshuri