I was having the same issue with the Full Width Wrap, and uploaded the file you had in your custom.pagebuild-fix-fullwrap.zip file (which I downloaded from this thread).
It *sort of* works now, but only if I selected “Boxed” as my website layout — not Full Width.
Therefore, I cannot use Page Builder’s full width wrap to set a nice image as the background for the in-page full-width wrap. If I do, then it conflicts with the background shown in my Boxed site layout and just looks wrong.
Is there a way to do Full Width website layout + in-page full-width wrap with an image as the background?