How the distortion looks like is highly dependent on the employed heightmap. Image 2 for instance was created by using another texture (which was set as Source Texture) as heightmap source. The Generator/Water function was applied to that texture beforehand. In contrast, Image 3 and Image 4 were rendered with the Use Mask option enabled.

Increase the Pre-Smoothing parameter to create bevelled and smooth distortions.

The size of the computed neighborhood is controlled with the Radius parameter. Increasing this value results in smoother transitions, but also in a greater distortion strength.

This can be compensated with the Amplify value. It directly regulates the distortion amplitude.