So, i just started to make sum maps and using the Terrain editor allot.
The problem now is that, when i invite my friend to make the map with me, She cannot see anything i made with the Terrain Editor, The world is just flat. Same with the Foliage editing, She cannot see anything that i have made on the world.

We tried to make a complete new world, I build a hill with the terrain editor.
She sees that, and thats good.
I save quickly, Restart the lobby.
My hill is still there but for she it's once again gone

Is this a bug right now or what is going?