1) you mean in the game or the editor?
2) I think that is just the small lightmap resolution used in the editor preview (but I can only guess without seeing the map)
1) When you play in gmae and the map is labeled as preview, you have automatically the ability to fly around with noclip by pressing CTRL. If you got in water, you get stuck at the base level and you can't go up afterward.
1) oh ok - sorry I thought I fixed that before
