I have also a problem with piklist and the SiteOrigin builder like this post.
https://piklist.com/support/topic/class-piklist_revision-issue/
The page will always save as a standard template when using the page builder. Now I want to build a new website and I’m testing with Thrives Architect. This builder will not open when Piklist is Activated! Thrives did look at the backend, and advise me to ask here for a solution. I’m using version 0.11.4