I was a bit devastated to learn of this limitation as I too was planing on building the world in stages in-between my players weekly game. However I think I've found a bit of a workaround (currently untested).

1) Prepare the first part of your campaign.
2) Have your players play part one.
3) At the end of the session save the game.
4) When you want to add the next lot of content use load from the GM Mode menu rather than Prepare.

You'll be in play mode (not prepare) but I've not found anything I cant do in that yet.

I've not tested this yet with players. But really hope it works as I think or my epic on going campaign is out the window.

The only downside I can see to doing this is the changes you make would not be present in the base save so if you were planning on publishing that to the workshop for others to play your edits would not be there


Last edited by sedilis; 19/09/17 01:31 PM. Reason: spelling