Broke my website

I installed it and wasted hours setting it up. It wouldn’t accept any other pages but the default Cart and Checkout pages. Whatever I put in, next time I went in the Settings, it was back to the default. The style of the shop, cart and checkout were ugly with no way to customize. But within a couple of hours, my system started to slow to a crawl, then returned 500 server errors and out of memory errors. In the occasional times when I could login, I saw that this plugin had created close to 1000 new pages, all duplicates of the Cart page. It must have been in some sort of infinite loop, creating more and more Cart pages. I deleted the plug-in and lost all the work configuring it, and will be up all night removing these duplicates and hoping my site gets back to normal again.