I have the same issue, it started in V33.00.
It works the first time and then I get this error everytime I try to launch session for the next 16 ish hours.
Ending game also causes “editor is not connected” so I only get one test per day. Create private code also does not work for me. Does it work for you?
I wonder if this could be the issue - when clicking build landscape I get 10000+ errors of that static mesh has null static mesh property, also how could I fix it without replacing every actor manually?
those yellow warnings in the Build Landscape are normal and can be ignored, do a Build Landscape again and use the SHOW button on the bottom of the window to deselect the warnings, see if you get any red errors.