Buoyancy example under engine contents dropped in not working

I dragged the buoyance example BP onto lake water in scene and on play, the cube falls through water, what might cause this ? I was having trouble setting up buoyancy in my BP acc to doc page on subject, and thought I’d try example in engine folder. Glad I did not even that is floating on water surface as expected.

Fix ?

Not using custom body water is key, but using lake, terrain is horribly deformed even far off around lake item. IS there a way around that ?Even if I disable that on lake object, it still deforms parts of terrain.

Also, I’d rather use custom body water as it does not deform surrounding terrain, is there a way to do that ?