Downloaded Enfold again from ThemeForest, uploaded via FTP and now it works – it’s almost annoying :) …could it be that there is a difference between the “All files & documantation” and “Installable WordPress file only”?

Exact same problem here, page works but the builder is in a spinning loop. I tried different browsers, troubleshooting mode and activated debug mode, but it’s still spinning…

add_action('avia_builder_mode', "builder_set_debug");
function builder_set_debug()
{
  return "debug";
}