how can help me with my 2 problems in the MMH7 editor?

First problem: I have different water depths, which are not visible on the surface, but which make problems. Who can tell me how I can bring the various water depths back to normal water level?

Second Problem: I have suddenly on my map in a area white surfaces instead of my painted texture, which is synonymous in the game too
Are seen. Who can tell me how I bring the away or where the problem

How can I fix the problem in Unreal Editor mode and in normal mode!

I would be glad if someone would help me there!