I've pasted an unlisted YouTube Video I made fairly quick to give a visual reference to the issue I believe myself and others might be having with the new Terrain Editor. Might also be caused by the Water update as well. Apologies for my camera overlapping the tool lol. I felt as though it would be easier to explain if the issue could be seen upfront. Please let me know if I may be using the tool wrong or if this was intentional.