Items should disappear from cart after purchase. The purchase information will be in your account. If you install the Reallusion Hub, you can download your programs there but if you already own the programs, the content you purchased will show up in the content manager in Character Creator - refresh the content manager via the two arrows forming a circle, your content will show in recent purchases or purchased items for quick access.

I'm not Reallusion staff, just trying to make your experience easier.