Widgets Page Not Loading After Installing Custom Sidebars Pro

Hi.

I have installed Custom Sidebars Pro on my website and have used the clone feature on the widgets. There are currently 67 unique sidebars in the widget with 138 widgets (many of them are cloned).

However, now the widgets page is not loading. There seems to be some problem with the Custom Sidebars Pro plugin as when I try opening the page without that plugin, it loads just fine. Can you please look into this matter?

Regards.
Himanshu