Guys, I made a huge mistake. I unfotunatly clicked on "burn Terrain" under image and now my whole map has black ground.
Does someone know how to redo this?

Go into the lighting tab and set the top and bottom lights settings on the right side to 255,255,255 and reburn the terrain. What that does is it sets the world lighting to 100% which should get rid of anything burned. If you had other settings there save the newly reburned wld first. Shut down ZE and then reopen your map and change the lighting settings back to what they were.