Hello ACF,
Same issue
Was hoping to find a solution for below:
http://support.advancedcustomfields.com/forums/topic/incompatibility-with-page-builder-siteorigin-editor-disappears/
I was able to go to my dev site – deactivate Advanced Custom Fields – and the page builder was able to load. Unfortunately this is not a fix as much of the site content is contained in ACF.
Any ideas?