Hello Eric,
My questions pertain to formatting. Is there a way to move the "addons" (as they are described in SP Page Builder), so that the formatting of the product page looks like the image I've attached? I did try to do this by rearranging the addons in the Products page of SPPB, but after I saved the page the changes do not show up in the live site.
To assign the custom SP Page builder page to the product, kindly go to Sellacious backend > Categories. Go to Templates and there select the templates you want to assign for product or category layout. You can assign these layouts to the parent categories and this will work for all the products assign in this category and its child categories.
As for the colors of the product title, pricing, buttons, you can change the preset color to the one you want and it'll change the primary color of site to the one you want. If you want to do it only for the shown parts in screenshots, you'll need to this manually.
I hope this helps.