This plugin keeps taking my site down! Please help!

Version 3.8.13.3
When I try to set the featured image on a new product, it takes the whole site down, with either a 500 error or – Fatal error: Out of memory (allocated 9175040) (tried to allocate 30720 bytes)

Please can you tell me why it’s doing that and fix it? I want featured images on my courses.

https://www.ads-software.com/plugins/wp-e-commerce-featured-product/