Larian Studios Forums Divinity - Original Sin Divinity Original Sin - Mods Running new level in editor

Ok I'm totally lost on something that should be very easy to do. I try to play a level I created in the editor. Here are my steps:

Create a new level with a name (EmptyLvl).
Create a new terrain (64x64, TR_Cyseal_Base).
Hit the yellow fellow or ESC.

I just end up with a black screen with the ui visible (character portraits, skillbar, minimap, etc.). I can do things like going into the inventory.

I can see the players standing on the terrain so I tried generating the AIGrid but i only get the 4 yellow squares around the characters and the rest is still red.
What am I doing wrong here?