There is no specific option in the theme for the shop, single product, and payment page layouts to set. The option you set from the “General >> Layout” will work on the entire site.
If you take that off the layout will be the one that you want for the pages and yes you can create different headers for the site pages you want.
Here is the video to learn how to create multiple headers: https://www.youtube.com/watch?v=BpeXfzNwkOc&t=11s
I hope it helps to solve your issue.
You said (And is there a way to make these images fit in the shadowbox when this page is full width?)
In my very first response, I already told you from where do you set the product image size read below.
This was my message: “To set the product images size to navigate to the Dashboard >> XSTORE >> Theme Options >> WooCommerce >> Product Images and from you will be able to set the product images size check the image: https://postimg.cc/5XXFdcmH”
Today you asked again the same thing and I checked your site and
I set the settings in that option and you can see the results in this video: https://streamable.com/p5miys
Hope this helps.
Regards 8Themes Team.
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.